=================================================================
This files constitutes the text of "Computer Adventures, The
Secret Art".  Following Bruce Sterling's example with "The
Hacker Crackdown", and cribbing some of his ACCEPTABLE USE POLICY,
I am now releasing the text of the book as "literary freeware".

Amazon Systems, who originally published the book, have approved
the electronic distribution of its text in this form, and, indeed,
expect to make a number of sales of the actual book on the back of it!
=================================================================

ACCEPTABLE USE POLICY

The documents on this disk are not commodities.  They're not for sale.
You didn't have to pay any money to get them.  If you did pay anything
to see this stuff, you've been ripped off.

You can copy them.   You have my permission to do that.
You can upload them onto boards or discussion groups. 
Please do!

You can print them out.

You can photocopy the printouts and hand them around as long as you don't
take any money for it.

But they're not public domain.  You can't copyright them as I've
already done that.  Attempts to pirate this stuff and make money from
it may involve you in a serious litigative snarl; believe me, for the
pittance you might wring out of such an action, it's really not worth it.

And don't alter the text, either; that would be pointless.

It's a couple of years since I wrote the book, so I've added
notes between *** *** where my opinion or where facts have changed.

Mail me and give me your opinions, if you like.

=====================================================================

If you'd like a copy of this book in its original paperback form,
signed by the author, typeset!!, very much easier to consult than
a pile of printouts, with full colour cover art and full of super 
illustrations from Andrew Hill, telephone, email or write to:

Amazon Systems,
Lodge Hill Road,
Farnham,
Surrey,
UK GU10 3RD.

tel (+44) 252-716669

Cost UK pounds 3.00
     US dollars 4.50
     UK post free
     Overseas Post UK pounds 1   US dollars 1.50

     VISA / Mastercard accepted for telephone/postal orders.

Gil Williamson  August 1994.

gil@cix UK

Compuserve 100271,761


 
               Chapter 1

               Introduction to the Secret Art

There is no doubt that the writing of adventure games is an art, in 
the same way that writing a book or play is. It is also a secret art 
in that a only a handful of game writers seem to be able to produce 
a gripping game.

I have carefully analysed the features of successful games, and present 
them here in the form of a Do-It-Yourself manual. This book reveals 
the secrets of how to plan, how to write and how to sell computer 
adventure games, also called `interactive fiction'. Irrespective of 
whether your game is a pure text adventure - for some the only `real' 
adventure - or a real-time graphic adventure, or even a text adventure 
with graphic illustrations, the principles of design are very similar.

Is there any point in trying to break into this difficult marketplace? 
Most certainly. There is a shortage of games with the essentials of 
a good adventure, which are plot, atmosphere, challenge and a sense 
of winnability. Advances in technology are much less important to 
the adventure game enthusiast. 

 Although the book assumes that you have played one or 
two computer adventure games, and that you therefore understand their 
general structure, it does not assume any programming knowledge. Some 
basic definitions are given in the table overleaf, and the chapter 
on Architecture describes and defines the various elements of an adventure 
in more detail.

  Terms used in this book:

A `Game' takes place in:

`Locations' (or Scenes or Rooms).

`Characters' (People, Monsters etc.) populate the Locations.

 An important Character is the Player
 Character who represents the game player.

`Items' (or Objects or Nouns) are contained in these Locations or 
may be in `Limbo' - a sort of storehouse for Items whose location 
has not yet been decided - or may be within another Item, or may be 
carried by a Character.

It is also possible for a Character to be contained in an Item.

The player interacts with the game by means of `Commands' input by 
keyboard or other input device.

              A Sexist Note:

In this book, for simplicity, I have used the terms `he' and `him' 
in reference to the player. I do, of course, realise that many ladies 
of the feminine gender are also players, so please accept `he' as 
`he/she' and `him' as `him/her' throughout. 


               Chapter 2

                   How to Present 
       your Game 
- Text or Graphics?

Most of the comments made in this book are relevant to all types of 
adventure, however presented, but there are always pros and cons. 
This chapter outlines some of the choices and consequences of  adventure 
graphics and sound.

              Presentation 

Often, the game-writing system you use will have as much influence 
on the format of your game as anything else. There are some notes 
about game-writing systems in Chapter 6, and in Appendix A. Ensure 
that the medium you choose is adequate to the adventure you plan.

In most adventure games, even those with considerable graphic and 
audio illustration, text is also very important. When you play a text 
adventure game, you probably find that the scenes you create for yourself 
in the mind's eye are just as vivid as any screen image could be.

A new genre of `arcade' adventure games is now becoming available, 
but for the few game writers lucky enough to belong to companies prepared 
to invest in these products, there are still many size and portability 
restrictions that are not experienced by text game writers. Writers 
of arcade adventures would do well to heed the tenets of good design. 
Razzamatazz may sell an individual game, but it will not sell a series.

Think carefully before deciding your game needs graphics. After all, 
though it is possible to print lavishly illustrated books much more 
cheaply nowadays, publishers seldom, if ever, think of illustrating 
a detective novel or book of short stories. In the computer world, 
though word processors and spreadsheets are presented in ever more 
elaborate guises, the properties of late 1970s Electric Pencil and 
Visicalc are still the important elements of these products.

Any game written for a particular piece of hardware will transfer 
most easily to other hardware if it is text-only. The cost and difficulty 
of transfer from machine to machine increases in direct proportion 
to the sophistication of the graphics and audio effects delivered.

Again, many computers in common use, such as IBM PCs or VAXes have 
little or no graphics or sound capability when compared with Atari 
and Commodore games-oriented hardware, and text adventures have become 
a favourite with users of such machines.

              Images:

The technology of screen images, together with the restrictions of 
RAM, backing store and development time, lead to three main types 
of graphic associated with an adventure that can be played on a personal 
computer:

     Hand-drawn still scenes of greater or less quality, 
sometimes with the facility to include characters and items that the 
player character can see;

Digitised still images (sometimes grouped so that a cyclic movie- 
like effect can be delivered);

Arcade-style playfields, sometimes drawn with perspective but operated 
in a 2-dimensional `Platform' format, where the player character, 
other characters and items actually appear, and move appropriately. 
The player character can manipulate the screen environment. 

Adventures with still or almost still images often allow the user 
to switch off the pictures, so that the user is reduced to a text 
adventure, with a better response time and more space on the screen 
for informative text.

In the `playfield' style arcade adventure games, or those which depend 
on the use of icons and mice and menus, the total number of locations 
in the game is often restricted, as is the richness of the game.

Some graphic games, I feel, are rather spoiled by having all possible 
verbs on pull-down menus, leaving little or no scope for imagination 
on the part of the player, and there comes a point where real-time 
events are happening on the screen and the game is verging on an arcade-style 
game, or a wargame.

My own personal opinion is that text is the most suitable medium for 
adventure games, but that optional illustrations, well-designed, can 
enhance enjoyment in the same way that good illustrations in a book 
do. Having said that, the shareware game-writing product AGT, which 
I favour, is text only.

In any event, the aspiring adventure writer will find that most game-writing 
systems currently available concentrate on delivering a text adventure 
(with optional still graphics). 

*** One or two systems for graphic adventures are now beginning to
emerge ***

Before leaving the subject of image, it is worth mentioning a useful 
advance on the old scrolling screen technique used in the early adventures. 
This is the `windowing' technique which allows the screen to be broken 
into various sectors such as:

     - Text from the game
- Graphic
- Inventory
- Command
- Exit directions
- Map
- Player status.

Some of these windows may be multi-use - the graphics and map window 
often being the same one.

              Sound Effects and Noises Off:

Though sound may sometimes be used to enhance a game, it is a mistake 
to make proper play dependent on sound. This is not because some players 
are deaf, or want to play while wearing their personal stereos, but 
because adventurers may not wish to disturb those around them with 
synthesised dalek voices, beeps and  laser  blasts. In  my  opinion,
sound  should  always  be capable of being switched off without spoiling
the game.

*** The advent of sound boards is allowing sound to become more useful
and usable ***


               Chapter 3

               How to get your Ideas

              The Style of your Adventure:

There are a number of clear forms in which an adventure can be placed. 
The first, and most common, is the one devised for the original Colossal 
Cave adventure. Each scene and its contents are described or drawn, 
and the player is free to attempt to move around, pick up and drop 
items and take action.

In the second form, a simpler one, the scene and contents are described 
or drawn, but the player has a very few alternative actions he can 
take. These alternatives are made clear to the player, and he simply 
selects alternative 1, 2, 3, or 4 etc. The consequences of each alternative 
tend to be more far-reaching than those of the other style of adventure. 
Such adventures resemble those children's interactive books which 
have a page for each situation, and where the reader is invited to 
turn to different pages to see the results of the various actions 
he can take.

A third main stream of adventures is the `role-playing' analogue, 
where there is emphasis on companions working as a team, and attributes 
such as strength, dexterity, stamina, and intelligence are given to 
each character. Magic spells and random combat play a strong part 
in such games, and it is sometimes possible for the player or players 
to act on behalf of more than one character in a single playing session.

 These three basic styles often merge and mingle with each 
other, but it is important to decide the style of your adventure before 
embarking on writing it and maintain the style throughout.

              Inspiration:

It is important to start with a new and different game concept every 
time. 

As you plot the game, it will keep trying to resemble other games, 
but you must resist the temptation to go along with these diversions. 
The 1988 AGT Game Contest featured a game based on a Wagner Opera, 
and another based on an SF short story. Both were original concepts 
for an adventure game, and made you want to play them in a way that 
a clone of Zork would not. 

On the other hand, there is always room for a well-written satire, 
though PORK has probably spelled the end for Zork satires. It is so 
important that your player's enjoyment is not dependent on him having 
played a certain game.

I have plot outlines for dozens of games, ranging from the ascent 
of mountains to underwater treasure hunting, from a journey on the 
London Underground system to a quest in classical Greece, from a round 
of golf to an E E Smith-style Space opera. I keep them in a spiral 
backed notebook, and keep adding ideas as they occur, until one becomes 
unrefusable and it spills out into implementation. There! I've given 
you six ideas in one breath, none of which closely resemble any game 
I've played.

Very few adventures even remotely approach realism, which is why it's 
a good idea to base them in an artificial, or at least very constricted, 
world. Use consistency in creation to communicate the atmosphere.

An idea should appeal before you consider it for game status. Whenever 
I enjoy a book or movie I consider how well it would translate to 
a game. Occasionally, something will just hit the spot, and it becomes 
a feature of one of your games in the pipeline. The London Underground 
concept grew out of a idea to optimise tube travel in London, not 
a game at all. The quest in classical Greece came from a Sprague de 
Camp book called `An Elephant for Aristotle'. As an ardent, but inexpert, 
golfer, I find that the situations one finds oneself in on a typical 
round more closely resemble `Lurking Horror' than they do `Leaderboard'!

One subject which can be rather delicate is Pornography. In particular, 
Leather Goddesses has a mildly pornographic theme, handled, I think, 
quite tastefully and amusingly. Leather Goddesses takes care to allow 
female players, and delivers alternate text and characters for them. 
Other games which go into much more detail on the mechanics of sex 
are much less appealing, and often insulting to female audiences. 
The buyers of such games would not be the mainstream of adventurers, 
and the games lack subtlety, even when compared to `girly' magazines.

 Once an idea has come to you, you must nourish it for 
a while to give it full value. What you do is to add all the extra 
features the game will support in the form of a `bull session'. In 
this manual, Chapters 4 and 5 are a huge mine of ideas on which to 
base plot elements. I work best by myself, with the Hi Fi turned up 
loud and a pencil and paper in my hand. Drawing a map will often suggest 
other features and plot elements. Reading the book that sparked the 
original inspiration may feed more ideas, and reading books on a similar 
theme should also help. Working with a like- minded friend is also 
a good technique.

              More Theme Ideas:

     The Happy Return:  
Instead of starting the adventure at a point before the quest begins, 
try starting it where the precious item has been recovered, and the 
player has to fight his way back to civilisation. This technique is 
useful for putting the player into the thick of the action early in 
the game.

Breakout: 
A similar idea is to start the game with the player imprisoned in 
some way, and he must escape.

Break-in: 
Penetrate the enemy defences, and free the prisoners - the Teheran/Entebbe 
approach.

Instruction: 
Make your player find his way around the ruins of Knossos, examining 
wall paintings and artefacts.

Expert System: 
Most adventure-writing systems can be used to develop complex diagnostic 
programs for simple situations.

Skirmish:  
Try setting the scene of the game as a relatively unimportant incident 
in a huge Worldwide (to hell with the expense - make that inter-Galactic) 
campaign. This is a super lead-in to a series!

First Contact: 
Explore unexplored territory, excavate archaeological remains, meet 
strange alien peoples and try to avoid shooting them. Have the adventurer 
find some peaceful contact mechanism.

              

              Basing your Adventure on an Existing Work:

Whereas in the USA, a copyright owner has to register his copyright 
formally and announce it on the work, in the UK and Europe generally, 
copyright infringement can take place even on unpublished work.

Copyright is not given to ideas, plots or themes, however original.

In the UK, copyright is infringed by the reproduction of any substantial 
part of a copyright work without permission. `Substantial' is hard 
to define. Even a very small quote can qualify if it is important 
to the work as a whole.

In the USA, copyright is infringed by quoting sections of a copyright 
work except for the purposes of non-commercial scholarship, comment 
and news reporting.

Therefore, although it is tempting to use an existing work as your 
basis, you must be extremely careful not to infringe copyright. It 
is a shame to devote lots of work to a game that can never be published. 
It is, perhaps, safer to write an adventure `..in the style of...'. 
Excellent examples of this genre exist.

Another pitfall is provided by Trade Marks. You will find that the 
inspiring name or phrase you might like to use in your game title, 
such as `Batman', `Star Wars', `Dungeons and Dragons', `Popeye' or 
`Lord of the Rings' is someone's registered trade mark, so steer clear 
of  these, too.

Apart from Copyright or trade mark infringement, there are a number 
of problems with using an existing work as your basis. If a player 
has read the book, or seen the movie, he will expect a resemblance 
between your plot and its plot. If you reproduce the plot of the work, 
then it becomes easy to solve. If you don't, the player is disappointed. 
Again, no adventure game, text or graphic, will exactly reproduce 
a book or movie. What the adventure game specialises in is the interaction 
of the game with the player.

I can well remember having a lot of `wheelspin' at the start with 
The Hobbit and other Tolkienesque adventure games, just because the 
plot didn't turn out the way I expected. Another disadvantage is that 
the solution to a problem in a book or film is often based on a character 
having a bright idea out of the blue. This is difficult to suggest 
to the player without broadcasting the solution or is boring to re-enact 
in the adventure.

Probably the best middle course is to borrow the atmosphere and technology 
from your chosen work, but to build your own totally new plot into 
it. 

               Chapter 4

               The Plot Thickens

Adventure games offer a feeling of involvement and interaction which 
can surpass even the most exciting book or movie, and it seems a pity 
not to make the most of them. This chapter contains over thirty main 
categories of feature, each of which can spawn hundreds of plot elements.

I advise you to work out a plot before you start writing the adventure. 
I say A plot, not THE plot, as you may contract, extend or modify 
the plot as development continues.

If you sit down to write an adventure from beginning to end, it will 
be a very thin and insubstantial piece of work. You need time to develop 
the theme and plot. 

I carry around a spiral-backed reporter's notebook - the poor man's 
laptop - which goes in my briefcase to work, sits beside me as I earn 
my living, and sleeps on the bedside table at night. Every time I 
have one of my brilliant inspirations, I note it down before the damned 
thing escapes again. In fact, a sharp pencil with an eraser on the 
end and a trusty notebook are better than a laptop for this purpose 
- I've tried both systems!

Into this notebook go the maps, the characters, the clues, the traps 
and the problems for the next adventure.

I find the maps to be the most fruitful source of inspiration. Very 
often, a map or the plan of a building can suggest a plot element 
that no amount of abstract thought could generate.

It is also handy to jot down character attributes so that you can 
keep the personalities consistent.

A good adventure does not just fall into your hand like a primed hand-grenade. 
It requires a lot of preparation, thought and creativity.

If you finish writing the adventure with the same set of plot elements 
as you started with, then you have every right to be surprised. Given 
a good basic theme, the very act of developing the details of the 
adventure should suggest other plot elements, which will gradually 
displace some of the original ones. There is nothing wrong with this, 
provided that you retain the basic theme. If that goes, then you either 
have an unstructured monster on your hands or the theme for another 
adventure!

It is no longer sufficient, these days, for a player merely to survive 
all the elaborate threats to his life. There must also be a story 
which is very nearly interesting enough to enjoy for its own sake. 
Atmosphere is also very important and there must be a build-up of 
excitement during game play.

Inject a minor dose of suspense early in the game, and up to three 
or four more important forebodings or anticipations before the end 
of the game. For correct dramatic effect, the last such event should 
be the biggest and best.

More will be said later about clarity and consistency in developing 
adventures, but much can be done to help development by keeping the 
plot well-balanced and paced.

Make sure there's enough territory around which the adventurer can 
roam to keep him interested at any given time. An adventure that starts 
in a cell and stays there until the player figures out how to escape 
will bore the average player quickly.

 Similarly, leave lots of items for him to play with, and 
don't make the adventure too lethal. It is very boring for a player 
to be killed off every time he makes a false move.

              Plot Elements:

To get you started, I've listed the following features to help you 
build your plots.

Try to introduce as much variety as possible to every adventure. Many 
of the ideas in this section are tried and tested, and some are totally 
new. Combine these ideas with your own and try to dress them up in 
a new guise.

         Possession of equipment: 

     One of the most typical requirements for problem 
solution is that the player be in possession of certain equipment. 
For example, plimsolls in Scott Adams' Pirate Adventure prevent the 
player falling off the window-sill. I remember this one because I 
discarded the plimsolls at an early stage and still managed to complete 
the adventure by SAVEing just before every trip to the sill.

Sometimes, simple possession of equipment is enough to make the game 
work. Sometimes the player must use the equipment in a certain way 
before it becomes effective.

         Collect and Assemble: 

     In many adventures, the player must collect and assemble 
pieces of equipment to make a new item. Again, in the Pirate Adventure, 
he has to collect all the parts for a galleon, and assemble them. 
This is the case where the combination of a set of items makes it 
possible to produce another item which the player needs.

Another neat feature is to require the player to keep the parts list 
with him in order for the item to be assembled. 

     In one of my adventures, one of the parts was omitted 
from the list. This part was necessary and should have been obvious 
to the player, but, just in case he hadn't realised, I allowed him 
to retrieve the missing item without too much further difficulty.

     Another typical game feature is to remove a part 
from one item for use on another - for example, taking a battery from 
a torch to make a radio work.

         Transformation:

     A favourite idea is to non-magically transform an 
item from one state into another by washing, cleaning or rubbing it, 
painting it, oiling it, winding it up, putting fuel in it, connecting 
it to the electricity supply, or switching it on or off.

     Very often the game-writing system will favour the 
switching of a non-working item with a working one, so that, although 
the player is theoretically unaware of it, the object is actually 
two items. The item in its first state is visible in the location, 
the other is kept in limbo. When the transformation occurs, the items 
are switched.

     Such transformations are not limited to items. Characters, 
including the player character, can be transformed into a new character 
in analogous fashion to Clark Kent & Superman, Popeye & Popeye with 
Spinach, Jekyll & Hyde, mild-mannered chemist & Incredible Hulk.

  

         Discovery:

     Often, an object which is available from a location 
is not visible when the player enters the location. The object must 
be discovered.

     For example, a game may require the player to dig 
in the ground or to move, say, a pile of leaves or a carpet, whereupon 
a new item is discovered. 

     Another favourite site for discovery is where a container 
clearly contains one item. Once that item is removed, another item 
is discovered lurking in the bottom of the container. You can hide 
items in unlit locations so that they cannot be discovered until a 
light is introduced.

     Again, from the game-writer's point of view, an item 
may be kept in limbo until the player carries out the action which 
results in discovery.

         Weapons:

     There are two basic types of weapons. A general purpose 
weapon, such as a loaded automatic, will be effective against most 
foes. A specific weapon, such as a wooden stake (anti-vampire) or 
a silver bullet (anti-werewolf), may be uniquely required to kill 
a certain class of enemy. Often, it will also be effective against 
other opposition, though the well-known vampire repellents - sunlight 
and garlic - seem specific to the undead.

     It is unfair to have a specific weapon in a game 
unless its effectiveness is widely known or there is some clue about 
it in the game itself.

     Another aspect of weapons is the number of rounds 
of ammunition they carry. This concept ranges from the six bullets 
in a magazine, through the number of arrows in a quiver and the charge 
(shots left) in an atomic blaster, to the potency of the magic remaining 
in an Elven Sabre.

         Apparel:

     A distinction is often made between items that are 
carried and items that are worn. The VERBs used might be WEAR and 
REMOVE. Clothes can be important for warmth, decency or as a mark 
of rank.

     Some items which are worn have even more special 
significance - for example Cloak of Invisibility, Space Suit, Gun 
Belt or Rucksack.

         Puzzles:

     A puzzle with a logical solution is a delight to 
solve. Examples abound in adventure games and represent a major source 
of pleasure in playing. 

     Suppose you have a game in which there is a radio 
without a battery, and a torch with a battery but a broken bulb. There 
is a clear invitation to make the radio work with the torch battery. 
This `collect and assemble' feature also represents a puzzle with 
a solution that makes sense. 

     Conversely, illogical solutions to puzzles detract 
from enjoyment.

     Another point to remember is that instead of trying 
to make an item work, you may want the player to stop an item working 
because it is interfering with his objective.

     Many of the features of adventure games present themselves 
as puzzles. The main thing to remember is to keep them fair. There 
is a class of puzzle so illogical that there is little satisfaction 
even in solving it.

   

         Bribery: 

     In this case, the player must find an item and give 
it to a character or monster in order to secure his/her/its co-operation. 
A favourite plot device is to allow several different items to be 
used to bribe a single adversary. Only one of these can, however, 
be spared. If one of the others is used, it makes the adventure harder 
or impossible to complete.

     Another feature of bribery is the need to carry an 
item so that a companion will stay with the player. For example, the 
player in Pirate Adventure soon discovers that the parrot will stick 
close to him as long as he carries the biscuits.

     Purchase is a special case of bribery. Some games 
allow a pool of money to be accumulated, usually by discovery of treasure, 
and expended in exchange for goods and services in furtherance of 
the quest. In this case, the pot of gold coins is depleted according 
to the value of the commodities purchased and increased by addition 
of treasure trove, plunder and swag.

  

         Mazes:  

     An adventure has considerable potential for the use 
of mazes but guard against making the maze boring. In some cases, 
the maze is a geographical one, in others it is logical. I shall explain 
the differences:

         Geographical Mazes:  

     In a geographical maze, if the maze is drawn on a 
piece of paper, the locations in the maze correspond correctly to 
the direction travelled to reach them. That puts them on a par with 
the kinds of maze you see in children's puzzle books. The way the 
game writer sometimes makes it difficult is to give each location 
the same or similar description. 

     To solve these, the player simply maps the maze. 
Extra complications can be introduced by having hidden passages which 
do not appear in the description.

     In Hollywood Hijinks, the author has a large geographical 
maze in which, when the player moves in a given direction, the game 
tells him how many paces he has taken before the next junction or 
dead end. A map is printed out as underlines and `I's, but it is in 
two layers - all the underlines, and all the `I's, and the two printouts 
must be overlaid before the whole maze is revealed. Nevertheless, 
because it is a geographical maze, it was possible to solve with only 
one layer of the map (as I laboriously proved), and would probably 
have been possible to solve with no map at all. Ah, what a feeling 
of satisfaction that accomplishment would have provided!

  

         Logical Mazes: 

     In a logical maze, the locations in the maze are 
connected together in a bizarre fashion so that a geographical map 
is not all that helpful. Typically, East from location A leads to 
location B, but West from location B does not lead to location A. 
Again, the locations may be similarly or confusingly named. Here is 
a diagram of such a maze:  

           Cave 2                             Cave 3
              ^                                   ^
              |                                   |
Entrance <- [Cave 1] -> Cave 2       Cave 1 <- [Cave 2] -> Cave 3
              |                                   |
              v                                   v
           Cave 3                              Cave 1



           Cave 2                              Cave 1
              ^                                    ^
              |                                    |
  Cave 4 <- [Cave 3] -> Cave 2        Exit   <- [Cave 4] -> Cave 2
              |                                    |
              v                                    v
           Cave 1                              Cave 3


     The quickest way from ENTRANCE to EXIT would be  E 
to CAVE 1,  S to CAVE 3,   W to CAVE 4 and W to EXIT. Note that if 
the player goes N from CAVE 2, he gets to CAVE 3, then N again returns 
to CAVE 2. Similarly, going E from CAVE 2 always takes the player 
to CAVE 3, and E again takes him back. If the descriptions of the 
four caves were similar, this would appear like an endless series 
of caves.

     The adventure writer's usual convention for these 
apparently illogical mazes is to call them `twisty' in the location 
description.

     Added variety can be provided by having the structure 
of the maze vary with time, or vary according to the player's activities, 
or at random.

         

         Variable Geography:

     Two or three examples of variable geography come 
to mind. In Wishbringer, for example, Festerton changes in a sinister 
fashion, part-way through the adventure. A totally new set of locations 
and items appears, each one a sinister version of the ones in the 
original Festerton.

         One-way and Restricted Exits:

     It is frequently useful to allow the player to pass 
from one location to another without being able to return the same 
way. Examples of this are some teleport devices (see transportation),  such 
as chutes, climbing down ropes, falling into pits or rivers and entering 
traps.

     Similarly, some adventures feature a narrow exit 
which can be negotiated by the player only if he is unladen or lightly 
laden.

     Too many such exits can prove burdensome to the player. 
Use the facility sparingly and logically. It is a useful feature for 
forcing the player to solve additional puzzles. In Sir Ramic, for 
example, the player enters a set of caverns by one route, but must 
leave by another if he wants to take the large item he has assembled 
in there.

         Secret Exits:

     Although a location description usually describes 
all the exits from the location there is no compulsion to do so. Therefore, 
an exit can remain secret by virtue of not being described, until 
the player invokes a SHOW EXITS command or tries a direction. A natural 
convention is to say in the location description `There are exits 
in many directions' so that the player knows he may have to try several.

     A useful `secret' exit is provided in a pond or pool 
if the swimmer dives. Then he can take an underwater passage.

     Another idea is not to have a conventional exit at 
all in the secret direction, but to `teleport' the player to the next 
location when he performs a certain action, such as moving a book 
in the bookcase or saying a magic word. Secret exits are therefore 
often one-way exits.

     Sometimes, a hint can be left that a secret exit 
exists, such as a rectangular hairline crack in the wall, or a character 
disappearing from the location unaccountably.

         Knowledge: 

     An important plot feature is giving the player knowledge 
which he can use to deal with an obstacle. For example, in Leather 
Goddesses of Phobos, there is a simple way of dealing with one of 
the monsters. To stumble upon that method would be very difficult, 
but deciphering a coded note gives you the information you need. 

     To maintain `fairness', some adventures with this 
kind of knowledge-based problem solution will not allow the knowledge 
to be applied unless the player has previously, in this particular 
instance of the game, encountered the item that offers the clue.

     A rather over-used ploy is to use a number written 
on some document as a telephone number or lock combination. See also 
copy-protection.

     Another knowledge-based ploy involves the player 
researching in reference books, or in the handbook supplied with the 
game. This method forms one of the principal features of instructional 
adventures.

          

         Curtains and Carpets:

     If you are concealing a scene or exit behind a curtain 
or wall hangings, then if the player moves the fabric, it must be 
replaced with another item which describes the scene or exit.

     A carpet frequently conceals a trapdoor, leaves cover 
cave entrances, and so on. The same sorts of description rules apply 
to these, and the simplest mechanism for the game writer to use is 
Transformation, described above.

         Elaborate Patterns of Behaviour: 

     Often, and this is most entertaining for the player, 
he must build up, by trial and error, an elaborate behaviour pattern 
to circumvent a single obstacle. A great example of this is the method 
of obtaining a Babel Fish in Hitchhiker, where the player must forestall 
several different accidents, and divert a robot before he can get 
hold of the fish. The messages from the game are humourous, and it 
is a pleasure to solve. In another commercial adventure, some elaborate 
behaviour is spelled out in a printed enclosure - acting as a sort 
of copy-protect mechanism.

         Richness of Methods: 

     Another entertaining feature is to provide different 
methods of achieving the same objective. In Paul Daniels' Magic Adventure, 
there were three ways of getting from the Airport to the Hotel - bus, 
taxi and hire car. All three methods worked, but each had different 
problems to surmount, and players were amused to hear about the routes 
they hadn't used. Another device to enrich a game is provided by giving 
the player a variety of roles to adopt, so that the story develops 
differently because of the different powers of the role taken.

         

         Door Openers:   

     There are lots of door-opening methods, ranging from 
the trivial KNOCK or RING to such elaborate solutions as a coin in 
the slot or solving a numeric combination. The classic ones are requiring 
a key to unlock the door or needing to say a magic word, like `OPEN 
SESAME', or having to show a pass. 

     Another complete set of solutions involves a door 
being locked until certain other doors are closed (as in an air-lock) 
or unlocked only for a certain period after another event.

     A door may be inscribed with runes or code of some 
kind which reveal the way to open it. The solution to the code might 
be a feature of copy protection.

  

         Riddles:  

     Riddles are a favourite technique. Make sure, though, 
that the solution you favour is truly unique and self-evident once 
guessed. There are two really annoying mistakes some game-writers 
make with riddles. The first is a riddle so obscure that it cannot 
be solved. The other is one to which you know one or more possible 
answers but cannot think of the words the game-writer expected you 
to use.

     An example of a `fair' riddle (Gollum in The Hobbit):

         Q. Alive without breath,
     As cold as death;
     Never thirsty, ever drinking;
     All in mail, never clinking.

A. Fish.


     An example of an obscure riddle:

         Q. What's green, hangs in a tree and
     whistles?

A. A herring. (see Polish folklore for the
     explanation of this)

     An example of a riddle with too many or complicated 
answers:

         Q. What's white and dangerous?

A1. Polar Bear;
A2. Blizzard / Avalanche / Iceberg;
A3. Seagull with a hand grenade...etc.

  

         Transportation:   

     There are wonderful varieties of vehicles in adventures, 
from magic carpet to teleportation device. If they are to be used 
repeatedly, though, make sure that they are easy to operate. For example, 
if you are only using a vehicle once, to make an essential bridge 
from one location to another, then it is fair practice to make it 
hard to operate. If, on the other hand, you are using it a lot, then 
it is boring to the player to have to, for example:

         PUT KEY IN IGNITION
TURN KEY
PRESS CLUTCH
SELECT FIRST GEAR
RELEASE HANDBRAKE
RELEASE CLUTCH

     .... and so on.

Peter Cartwright, in his new Lady in the Swamp adventure, accumulates 
a list of destinations for his car. Once the player has solved the 
clue for another possible destination, that destination is added to 
a numbered list with which he is presented when he suggests driving 
the car.

A number of anomalies occur with transportation. If the player character 
actually enters the vehicle, then commands like East, West and so 
on may really apply to the directions inside the vehicle. This is 
fine if the vehicle is large, like a spaceship, but not if it is a 
car, for example, when these commands might be appropriate for the 
whole vehicle and contents. When you are in the vehicle at some location 
or other, do you describe the location, or do you describe the interior 
of the vehicle? 

  

     There are two or three ways of dealing with this, 
as follows:

         If the vehicle is a horse or other vehicle which 
is not enclosed, then you can move it to the new location with the 
player in response to a direction command. In this method, the player 
has to be `on' the horse or `on' the motorbike. This you can ensure 
by forcing him to use a `mount' command, then setting a flag to ensure 
that he dismounts before he does anything other than travel from location 
to location.

If the vehicle is like a car, in that it is enclosed, but the outside 
world can be seen from it, it can be handled by having several locations 
such as `At the Town Hall in the car', `Outside your home in the car', 
`At the Beach in your car'. 

You move from `At the Beach' to `At the beach in your car' and vice-versa 
by ENTER and EXIT. Travel is effected by moving the player from one 
`... in the car' location to another. Elevators are also dealt with 
in this fashion.

If the inside of the vehicle is actually a set of locations like this, 
each with a different view from the window, then be sure when you 
`move' it to the Town Hall that you also move any items the player 
has dropped in it when he was parked at the beach, as well as reproducing 
any controls inside the car.

Also, ensure that the player can only travel between these locations 
by car, otherwise he will find on walking back to the Town Hall that 
the car he left at the beach has mysteriously driven itself to join 
him!

         Alternatively, you can implement vehicle operations 
by moving the exits around while the player is inside the vehicle. 
The vehicle is one location (or even a group of locations if it is 
a ship or spacecraft). This is handy if you are prepared to describe 
the journey rather than the destination. Some of the adventure game-writing 
systems will not allow this type of solution, as exits cannot be altered.

     Teleportation is a very handy system. Often what 
seems to be transport is actually teleport. The player is removed 
from location X to location Y. If the locations are not `in the vehicle'  then 
the vehicle must also be teleported. It is also used to deal with 
secret exits and resurrection, and is even a major feature of some 
games, such as Star Portal.

One commercial game has an ingenious `black hole' teleportation device. 
Entering any of the black holes takes you to a predictable destination. 
There is even one hole which the player must make for himself, another 
which is cleverly concealed inside something else and another whose 
destination moves in a predictable manner.

  

         Death and Resurrection:

     As cautioned elsewhere, try not to kill the player 
too readily. However unsuccessful his ploys, it is unfair to make 
them a capital offence.

Resurrection is a fairly frequent device to prevent the player from 
having to restart the game. For a serious player, however, it is unsatisfactory 
to win a game as a result of a resurrection and he would reload a 
saved game in these circumstances. If you do provide a resurrection 
facility, make sure that the game is re-set in a playable form. Sometimes, 
the game-writer maroons the player without access to the items needed 
to complete the adventure, which makes the exercise pointless. It 
is quite in order to make the game harder by scattering the items 
the player character carried in his inventory around the accessible 
locations at random.

     There are special cases where apparent suicide on 
the part of the player character or a companion is beneficial in the 
way that sacrificing a piece in Chess can be.

         Push, Pull, Turn and Play:

     Most adventurers, after EXAMINEing an item, will 
PUSH, PULL, TURN or PLAY it, depending on its description. Very often, 
this is exactly what the player was intended to do. However, it is 
always advisable to have some relevant responses to these attempts, 
even if they do not advance the game.

         Containers: 

     The use of containers can be extremely helpful, particularly 
when the contents are nested. In some adventures, there is a limit 
to carrying capacity which can be over-ridden by the use of a container 
to carry the smaller items. 

     Again, the difficulty of opening successive levels 
of container can provide a pleasurable experience to the player. It 
is also possible to perform cartoon-like incongruities in which a 
small item contains a very large one. 

The usual mechanisms for container manipulation are OPEN and CLOSE, 
but UNLOCK and LOCK may also be relevant. Most game-writing systems 
do not allow transparent containers, so that any contained objects 
are not visible when the container is closed.

         Invisibility:

     Invisibility is a very useful attribute for a player 
character. In this state, the player can usually avert monster attack 
and can eavesdrop with impunity.

Invisibility offers a great deal of scope for the author's imagination. 
The effect can be of short or unpredictable duration, may have adverse 
physical effects, and may prevent the invisible character from carrying 
or even touching items.

The invisibility can be invoked in a number of ways. For example, 


         magic spell
wearing a ring or cloak
consuming a potion.

     Remember to deliver handy clues regarding the invisible 
player's state and limitations, otherwise the benefit of invisibility 
may become almost totally incomprehensible to the game player.

         

         

         Codes & Ciphers:

     The easiest method of introducing codes and ciphers 
to a game is via a discovered note. Another method of making codes 
seem natural is the translation of alien languages or character sets, 
including runes. 
Most adventurers are quite capable of interpreting a message simply 
anagrammed, coded or ciphered. A typical trick for short messages 
is to take the message and transpose all letters in the following 
regular fashion:

         A-D; B-E; C-F; .... W-Z; X-A; Y-B; Z-C


     so that HELP becomes KHOS.

To make it harder, we could reverse or otherwise anagram the message, 
and/or break the message into regular groups. The purpose of this 
is to hide the identity of common words such as `a', `of', `to' and 
`the', so that translation cannot be based on recognising word length.


         HELP I AM TRAPPED INSIDE A COMPUTER 

     might become:

         HELPI   AMTRA   PPEDI   NSIDE   ACOMP   UTER 

     before being transposed to:

         KHOSL   DPWUD   SSHGL   QVLGH   DFRPS   XWHU.

     However, there is a limit to the patience of your 
audience. The method usually employed to decode transposed messages 
is to count the letters, and then assume that the most frequent will 
be E, the next T, then A, O, I, N, S, H, R, D, L, U and so on, which 
tends to work fine for English with the regular frequency of `the' 
`a' and so on.
If it is a regular transposition, the player assumes the most frequent 
letter is E, then T, then A and so on, until the message springs to 
view.

Let us analyse the message above:

 letter	no of occurrences
	E 		4
	A		3 
	I		3
	P		3
	T		2
	R		2
	D		2
	 and all the rest 1.


     Your player would have a reasonable chance of decoding 
that message if you used a regular transposition.

On the other hand, if the message is a long one, you can afford to 
have an irregular transposition such as:

         ABCDEFGHIJKLMNOPQRSTUVWXYZ

      matching to:

         XFJQZKESVDNPIUWHARTYOBCGMP

     for example.

You could even make the message very short and the transposition immensely 
complex if you overtly or secretly include the key in your game instructions, 
as I did in the Paul Daniels Magic Adventure or in a codewheel or 
other device in the game pack. (See also the section on Copy Protection.)

         

         

         Following:

     Many discoveries can be made only if the player follows 
a non-player character or monster to find out what he/she/it is doing.

It is especially useful to allow the player to eavesdrop on other 
characters in order to determine the magic words that open doors or 
quell demons.

Sometimes following will permit directions and paths which are not 
available to the player moving independently. In at least one adventure, 
following an animal is a good way to get out of mazes.

         The Senses:

     Smell and hearing can be useful adjuncts to an adventure. 
At least one adventure was issued with a `scratch and sniff' card, 
and Hitchhiker has a situation where the player must use senses other 
than sight to continue play.

Characters with heightened senses may be able to detect danger at 
a greater distance than usual.

         Proxy Actions:

     Actions which might be undertaken by a player may  be 
delegated to a non-player character, usually a companion to the player. 
This delegation may be made explicit by command of the player, or 
implicit by virtue of the presence of the character. 

For example, Trent/Tiffany in Leather Goddesses always performs spontaneously 
to protect the player character if he/she is present.

There is more discussion of this under the subject of Characters and 
Monsters.

         

         Time Dependence:

     Another important feature in adventures is time. 
For some of these, time is `real' time, but it is more usual for time 
to be proportional to the number of moves made.

Many adventures expect the game to be solved within a certain timescale, 
counted in turns, and close the adventurer down if he has not reached 
the end.

Important use can be made of the effect of time. For example, a maturing 
element can be introduced, in which an item transforms into another 
over the period of several turns. A caterpillar might transform to 
a butterfly. A seed, once watered, might grow into a plant.

Conversely, a leaking bucket might become empty within a few turns, 
or, most typically, a torch burns out after twenty or so turns. The 
torch device has been over-used in adventures, in my opinion, but 
there is no harm in introducing some new time- dependent wear and 
tear.

Finally, there is the `critical moment' feature, where something happens 
at, say, turn 27 of the game, or 27 turns after another event. The 
player must be ready for the event or he will miss it. It is important 
to inform the player that the event has occurred, or he may never 
realise he is too late.

Ambushes are often time-related. A non-player character intercepts 
the player on the basis of the number of turns performed or on the 
basis of the number of turns performed in a single location.

         

         

         Weather:

     Another feature which is often time-related, but 
probably deserves its own category, is weather.

Mist or Fog can reduce visibility. Cold weather might freeze the moat 
the player needs to cross. Hot weather might dry it up. The fire-breathing 
dragon probably stays home in rainy weather.

         Skills, Powers and Magic Spells:

     This is a very handy plot device. The player, or 
one of his companions, acquires the power to make a transportation 
device work, to defeat monsters or to control some other important 
feature of the game.

It can, however, make a game tedious if taken to extremes. For example, 
if the player has the strength to lift a ten-ton rock, it is inconsistent 
that he must use a key to open a door, or use a silver bullet to kill 
a werewolf. Surely he could apply a ten-ton rock or his Fist of Iron 
to either problem. While a role-playing Dungeon master can deal 
with frivolous use of powers when the game is played by people in 
a non-computer context, an adventure writer would be hard put to anticipate 
all possible misuses of a strange power. The power must be carefully 
constrained to a small range of effects.

 

         Logical Traps:

     Fiendish glee can be obtained from the delivery of 
a trap in the form of a clue. For example, watering a dry plant might 
transform it into a man-eating Arcturian Tiger Orchid!  Or the player 
might be tempted by a clue to bribe a guard, only to discover that 
guards react very badly to bribery.

Similarly, the game might tempt the player to use a piece of wood 
to break a window, only to reveal, when the player picks it up, that 
the piece of wood was supporting the ceiling.

         Physical Traps:

     Physical traps usually reside in a specific location. 
They may consist of, for example, a hole in the floor into which the 
player has a percentage chance of stepping, or a monster which lives 
in that location. Rock-climbing or Monster-killing equipment, respectively, 
might protect the prudent player in these locations. Traps should 
be distinguished from ambushes, where the danger stalks the player 
and may strike in a number of different locations.

The trap may either be passive, where it actuates either regularly 
or randomly without the player's intervention, or active, where a 
player has to do something incautious to trip it.

There is no limit to the ingenuity of the game-writer in delivering 
a trap. A falling rock or missile, a bright flash that blinds the 
player character or an illusory exit are just the tip of a large iceberg.

         

         

         

         Alarms:

     A variation on the Trap is the Alarm. Allow the player 
to trip an alarm by entering a location or doing something. This alarm 
can then set a counter which guarantees to bring the Horrid Goblin 
Hordes rushing to the scene very soon, and the player has perhaps 
three turns to escape or render himself invisible.

         Darkness, Obscurity and Illusion:

     It is natural to render a player vulnerable (to Grues, 
usually) and disoriented when in a dark room. The game-writer can 
decide whether the player can move out of the dark area, and how many 
turns he has before the grue descends upon him. A dark room can usually 
be lit by a general purpose light source, but it is often useful to 
make a room's appearance and contents visible only when a certain 
object - analogous to a light source - is being carried by the player. 
For example, a Helmet of Clear Seeing.

Another handy device is Obscurity. This resembles a thick fog in which 
the player can move around freely, but cannot find anything and may 
have to make several attempts to leave the location, often exiting 
in a direction different from that which was intended. Obscurity can 
accompany Ambush.

Illusion is an excellent feature. It consists of a location, item 
or character appearing different from reality (whatever THAT is in 
an adventure game). From the game-writer's point of view, substitute 
characters or items are used if the illusion is limited, or variable 
geography may even be used for extensive illusions.

         

         

  

         Ambushes:

     Ambushes are a type of trap in which a non-player 
character, such as the thief in Zork, mugs the player, often killing 
him. The exact location of the ambush is not necessarily predictable. 
It could be engendered by a time-related formula, by the value of 
the player's inventory or by the length of time the player remains 
in a certain location.

Typically one allows the player's possessions to be lost for good, 
or to be scattered around the locations of the adventure.

It is usual to allow the player to be able to ward off ambushes by:

         - reacting to the ambush by taking one of a
  number of allowed actions

- avoiding the circumstances which lead to
  an ambush - for example, by not standing
  still for too long!

         Helping Out:

     Sometimes it's a good trick to show a creature or 
character in distress. If the player helps that creature, the creature 
then, or perhaps much later, helps the player. It is a useful feature 
to make helping the creature optional at the time the help is required. 
In this way, there is virtue in providing the help and the subsequent 
reward is well-deserved.

         

         

         

         Clues:

     There are many ways of delivering clues.

Non-player characters can include hints in their conversation. In 
particular, lies and contradictions may provide oblique clues. Cryptic 
clues - like those in crosswords - may also suit a particular type 
of adventure.

Characters deliver hints in two forms - either as an unprompted statement 
like the loquacious parrot in Pirate Adventure, or on request as with 
the owl in Sir Ramic Hobbs.

The most direct method of delivering a clue is in response to a HELP 
request from the player. I would advise against inviting him to buy 
a hints booklet, as some games do. I always feel that HELP should 
provide an opportunity for the game writer to deliver a relevant hint 
or at least a meaningful response then and there.

Often a clue can be hidden in a riddle, but make sure it's a fair 
riddle.

The most subtle, and most satisfactory method of delivering clues 
is within the location and item descriptions. For example `The plant 
is dry and withered' is a clear invitation to water it.

A method which I used in Sir Ramic concerns the use of a magic carpet. 
There is a device which controls the carpet, but which seems to be 
intended for something else. When the player uses the device in the 
more obvious manner, the carpet whooshes away. This tells him, or 
should do, at any rate, how the carpet works.

         

         

         Food and Drink:

     There are two reasons for including edible and drinkable 
items in a game.

The first concerns the need for the player character to keep body 
and soul together during the game. As a player, I find it very tedious 
to keep having to go through such housekeeping activities time and 
time again. Game writers should make sure that the caches of food 
and drink, however hard to find, are sufficient to sustain the player 
for a considerable proportion of the game once taken.

The other purpose is to use comestibles to make important (usually 
magical) changes in body size, visibility, awareness, state of health 
and so on. Conversely, feeding suitable items to enemies may disable 
or kill them.

         Unusual Uses:

     A game is often enriched by providing an everyday 
object which is to be applied to the game in an unusual manner - for 
example, to use a food mixer as the propulsion unit for a boat.

Provided enough clues are given, this can be a very entertaining feature. 
Unfortunately, examples of bad planning abound. Some problems appear 
time and time again in fan magazines and bulletin boards.



               Chapter 5

               The Cast of
 Characters
 Assembles

An important component of any plot is the characters who must help 
the player act it out. While you need not have your full complement 
of characters before you start development, it is helpful to have 
selected the leading players, as they will suggest plot elements to 
the writer.

Characterisation is one of the hardest parts of adventure creation. 
There are few really memorable heroes or villains in adventures. This 
section should give you some ideas on how to create interesting characters 
and communicate their personality to the player.

              The Player Character(s):

There are no clear rules for choosing the attributes of a player character. 
That character is the one whom the player controls like a puppet, 
and who represents the game player's interests. 

In an arcade adventure, the puppet is usually clearly seen strutting 
around the screen, and text messages clarifying the situation are 
preferably kept to a minimum. Personal identification between the 
player and the character is often weak, because the figure on the 
screen does not look much like the player.

Even in an illustrated text adventure, the player character does not 
often appear in the graphics. In essence, the graphics represent what 
the player character can see. Since there is often an option to switch 
off the graphic image, the character's appearance on the screen must 
be non-essential to the characterisation.

In other words, the attributes of the character are usually communicated 
to the player by some intellectual process, rather than pictorially.

In my adventures, the quality and disposition of the player character 
are communicated by the way the game reacts to him. It is quickly 
made clear, for example, that Sir Ramic Hobbs is an unathletic, drunken 
character with considerable courage but a misplaced faith in his own 
capabilities.

As an author, you ought to give careful thought to these personality 
considerations, and, once the player character has been created, maintain 
a consistent reaction to him/her throughout the game or explain why 
the attitude changes.

              Other Characters and Creatures:

         Characteristics:

     The attributes of a non-player character or creature 
are communicated to the player by what they say or do, and consistency 
is again the watchword here. That does not mean that the character 
should be bad through and through or unwaveringly good. What it means 
is that once you have decided on the personality, don't let him/her 
act `out of character' without reason. As novelists have discovered, 
it is appealing if the baddies have a redeeming feature and the goodies 
some flaw in their personality.

It is sensible to assemble a set of characteristics, and give each 
character and monster a score out of ten against each characteristic 
in the style of a role-playing game. If desired, too, the profile 
and current condition of the player character and all the other characters 
in the game can be maintained throughout. 

     When the character is attacked, or goes without food 
or travels a long distance you can use his attributes to decide how 
he will take the strain and what his eventual condition will be.

This can be taken to the point of resolving combat with the use of 
chance factors, hit points, armour class and damage tables.

The effect of poisons, spells and cures can also be reflected in the 
attributes of the characters. TSR's excellent Dungeons and Dragons 
handbooks are a great source of inspiration for such logical world 
structures.

Health may be restored to an ailing character by antidote, spell, 
food & drink, sleep, infusion of old batwings and toadsbreath or the 
undying love of a fair member of the opposite sex (or even an unfair 
member of the opposite sex).

         Character Actions:

     Much of a game's enjoyment often springs from the 
seemingly independent action of other characters. These actions may 
be programmed to appear truly spontaneous, or to react to the player's 
actions or requests.

The spontaneous actions of characters can provide warnings or clues. 
For example, it is reasonable to cause a canine companion to detect 
the smell of enemies approaching, and behave in a way which warns 
the player.

  

     Hostile and murderous characters (often monsters) 
provide a great deal of the challenge of adventure games, but, unlike 
space invaders, it is not great sport just to zap them all with superior 
strength or by being lucky. It is more rewarding to subvert, trick, 
bewitch or befriend the opposition, sometimes with the aid of friendly 
companions.

The antics of the living (and undead) denizens of your world can provide 
entertainment, even when such behaviour does not directly advance 
the game.

         Proxy Actions:

     Sometimes, a player may cause his player character 
to issue an instruction to another character in the game. As the game 
author, this complicates your job somewhat, because you have to deal 
with all these sorts of action as well as the player character's own.

The complication has its reward in cases where a companion is able 
to distract or defeat a monster, working in partnership with the player, 
where the player would not have been able to win single-handed.

Alternatively, the non-player character, by virtue of some special 
characteristic, could be able to do something the player character 
cannot, like climb a rope, lift a great weight or cast a spell.

  

         Character Utterances:

     Similarly, the speech of other characters is often 
a very considerable feature of a game.

Use speech to communicate the attributes of the character, and to 
deliver clues to the player. These clues should be spontaneously offered, 
or offered in response to a request or as a reaction to player activity. 


I sometimes find it useful instead of writing:

          `The parrot says: "Watch out for the Jabberwock!" ' 


     to employ the dramatic convention:

          `Parrot: Watch out for the Jabberwock!'

     and indent the speech if it runs to more than one 
line. This distinguishes speech from location and action description.

     Characters may speak spontaneously or may respond 
to information requests and deliveries such as:

          `ASK PARROT ABOUT MAGICIAN' 

     or 

         `TELL POLICEMAN ABOUT THIEF'.

     Extra interest can be brought to the game if each 
character speaks in a different manner. In Hobbs, the narrator (Prang) 
speaks in a withering and sarcastic tone, while the owl always speaks 
in a grovelling, ingratiating whine. 

  

         Lies and Contradictions:

     Like real people, characters in adventures often 
lie and contradict themselves. These falsehoods often give the player 
an insight on the truth, or on the true nature of the character.

Detective adventures are the principal medium in which this kind of 
behaviour gives clues to the player, but there is something to be 
said for using the feature in other types of adventure, as a guide 
to personality or as a clue.

         Companionship:

     It is usual for the player character or hero of an 
adventure to be accompanied by one or more companions who may act 
on the player's behalf either spontaneously or on request.

It is often also possible for a player to choose to be a different 
character on a subsequent play of the game. Some multi-user systems 
allow a number of players to wander the realms of the adventure simultaneously.

As described under Proxy Action, it is possible to instruct different 
companion characters to perform actions that the player character 
cannot carry out. This is in line with the role-playing convention 
of sending a group of adventurers on the same quest, typically a warrior, 
a thief, a priest, a witch, a dwarf, an elf and so on.

It is common for companions, once encountered, to follow the player 
character everywhere. On other occasions, it is necessary for the 
player to press them into service by bribery or simply by requesting 
them thus:

         `THESEUS, FOLLOW ME'.

         Monsters:

     Beware of stereotypes in monster design. Every monster 
should be a well delineated character in itself. The fact that an 
ogre wants to eat the player character is not in itself evil. It is 
in the nature of ogres to eat adventurers, in the same way that it 
is in the nature of pike to eat perch.

If he is to be really evil, the ogre must be seen to kick puppies 
and pull the wings off butterflies. He may also have one robust redeeming 
feature like cheating on his taxes or selling his mother-in-law into 
white slavery.

It is these little points which make him a really rounded character, 
and a positive pleasure to lure into the path of a combine harvester.

Monsters can also have specific powers such as poisonous stings which 
act over a period of time, or the ability to become invisible or roam 
the locations or follow the player character.

As mentioned under Weapons, a monster may be vulnerable to a specific 
weapon as opposed to a general-purpose one. Equally, it may succumb 
to attack by a particular companion character, or it may have a vulnerable 
time of day, or the famous soft underbelly.

Monsters can range from pools of sentient corrosive slime, through 
renegade Asimov-eating robot, to God of Greek Mythology.



               Chapter 6

               How to Develop and Test your Game

Having decided on your theme and setting, and put together a plot 
and the leading characters for your adventure, the next stage is to 
actually develop the game, using the game-writing system or systems 
you have chosen.

The first part of this chapter discusses the__ art__ of conveying 
atmosphere and excitement to the player. Next, come some notes on 
the __craft__ of the game-writer. The third section concerns the 
__technology __of game-writing systems.

              Art:

The art of the adventure game writer bears a close resemblance to 
that of the short story writer. He must create an atmosphere with 
as few words as possible, and build and sustain excitement with economy.

How are atmosphere and excitement to be achieved? 

However inspiring the subject matter of the game, the key areas are:

     - Clarity
- Consistency
- Responsiveness
- Progress
- Reward
- Anticipation.

These are, in fact, substantially the same key elements as all games 
require.

         

         Clarity:

Except where obscurity or illusion are intentional it must be clear 
to the player, either in words or in graphics, what the current situation 
and objective are. In addition, it is helpful for the player to know 
the overall objective of the game, even if that objective is quite 
irrelevant to the current situation.

The geography of the game in general and of each scene must be clear. 
This is particularly important in graphics games where the constraints 
of the drawing method or the screen resolution can perversely make 
perspective and direction difficult to perceive.

Sometimes it is fun to conceal the true nature of an item, but most 
of the time you have to work quite hard to describe them clearly. 
Again, this can be hard in graphics games. A `zoom' or text feature 
is often necessary. 

Sometimes, a handbook issued with the game provides a detailed description 
of important items and of the geography of all or part of the game. 
This can also be a useful copy-protection device.

In writing and testing your adventure, you must always place yourself 
in the position of a `dumb' user who has not helped you write the 
game, and make sure that he will always know what his target is, what 
has happened, where he is, who and what are sharing the environment 
with him, and, to a large extent, his degrees of freedom to act.

         Consistency:

A game must be consistent. That doesn't necessarily mean realistic. 
Because few adventures even remotely approach realism, you rely on 
the consistency of an imaginary world. Consistency encourages the 
creation of atmosphere.

If an effect works in one part of the world, it should work in all 
parts. For example, your `dissolve rock' spell should dissolve rocks 
encountered anywhere in the game, not just on the wall you need to 
penetrate. Paint should make a mark wherever you daub it, not just 
where you need it.

The fulsome description or detailed graphics you deliver for the early 
locations should be maintained for all scenes in the game. If the 
quality is bunched at the start of the game, the whole game starts 
to look very thin. This is harder to achieve than you might think. 
By the time you are half-way through an adventure, the end will appear 
more distant than it did before you started, and a panicky haste will 
descend upon you.

If you are really restricted on resources, it is probably best to 
reserve the best graphics for the first and climactic scenes. This 
avoids the impression that the game is gradually fading out.

         Responsiveness:

Interactivity distinguishes adventure games from the books and movies 
which are much richer in other ways. It is important for the game 
to return a fairly high quality of response. `You can't do that..' 
is going to be returned all too often as it is. If you, as the game 
writer, can anticipate some of the ploys a player may try, it is certainly 
your duty to build appropriate responses to them, even if the player's 
action does not advance the game.

If his action is `getting warm' - for example, if he has tied one 
end of the string to the right lever - make an encouraging response.

 In arcade adventures, the antics of your player character 
are eventually going to become boring when a player is trying to retrace 
his steps. Make his response to direction control very positive so 
that the player can gallop through the areas he knows well.

         Progress:

The game must move forward to remain interesting. One way of doing 
this is to open up new avenues of exploration to the player. It's 
no good to move him from one anonymous cave to another. The new cave 
must be interesting in its own right. The player should always have 
a reasonably large territory to explore unless he is in a tight spot 
of some kind. There should be enough items and clues lying around 
to keep him interested for a while. As emphasised in __Clarity__, 
he should have a general idea of the geography and objective of the 
game, so that he can see he is getting somewhere.

Avoid tedious mazes and avoid killing the player too readily. Obviously, 
the player can use SAVE and RESTORE to anchor his progress, but it 
can be tedious to keep reloading in order to recover from sudden death.

Putting a `security lock' on the RESTORE verb can be all you need 
to dishearten a player from using a pirated copy. Going back to the 
beginning of the game after every mistake is even more tedious than 
RESTOREing. This can be the basis for copy protection.

Often, it is worth having a character appear and brief the player 
on the solution to a problem if he has been stuck in a situation for 
a large number of turns. I see no virtue in wandering the corridors 
of a dungeon for year after year, with nothing new ever coming to 
light, and the solution ever elusive. These games are meant to be 
interactive fiction, not eternal purgatory.

Make your clues meaningful. I have often delivered a clue that seems 
as broad as a barn door to me, but which turns out to be too subtle 
for my audience. Remember, you know what the solution is. Your player 
is going to have to work much harder than you, and if he fails to 
make progress, he will become bored. This is a difficult balance. 
You must maintain the impression of progress for the inexperienced 
player, while giving a challenge to the Seventh Dan adventurer. In 
short, an adventure game should be challenging, but not unreasonably 
difficult to play.

Apart from any other consideration, it is a terrible waste of your 
own creative spark if most players never reach the end of your game. 
That would be like an author expecting most of his readers never to 
reach the end of his novel.

         Reward:

Reward is the mechanism by which the game author can indicate progress 
to the player. It is also a mechanism for keeping the player interested 
even when he is actually making no progress at all.

It can vary from the opening up of a new and interesting set of caves 
to the appearance of a new character or an amusing consequence of 
something the player tries.

Nothing keeps a player interested like a well-communicated sense of 
`winnability'. If he really believes he can complete the game, he 
will work much harder than if he constantly feels discouraged.

Often, alternate methods, one clever, the other laborious, of solving 
the same problem can be used to give the player confidence that he 
will solve all the puzzles one way or another, or that he doesn't 
just have one chance of winning.

It is useful to use different responses (selected at random) to reply 
to different instances of the same or similar stimulus. This keeps 
the player trying much longer. If the invariable response to `TOUCH 
item' is `Nothing happens' then the player will become bored more 
quickly. He will keep playing around with the items in a more creative 
manner if the responses are richer such as: `You'll take the shine 
off it!' or `Careful how you touch the ...'.

Another way of rewarding the player is by giving him points for progress. 
Points scores in an adventure are, however, less motivating than they 
are in an all-action arcade game. Nobody plays adventures for the 
pleasure of seeing their points score, though it is often used to 
measure whether the player has completed the whole adventure. It __is__ 
important to make it clear to the player that he has completed the 
adventure, by making a positive statement to that effect.

         Anticipation:

Nothing builds excitement like anticipation. It is a vital element 
of any successful game. If you can convey to your player that something 
exciting is going to happen before it does, you will add greatly to 
his enjoyment.

As described in the chapter on plotting, there should be a build-up 
of suspense throughout the game, consisting of events which are anticipated.

The character of these events, and the manner by which the anticipation 
is delivered will vary from broad hints like `You can hear the tramp 
of iron-shod boots approaching' to more subtle clues such as small 
animals scurrying in the opposite direction and `an unnatural silence 
descends upon the countryside'. Alternatively, you may give the player 
hints of something wonderful on the opposite side of a canyon that 
he must cross, or the form of the geography may indicate that he is 
about to stumble upon an important discovery.

Surprises are very much part of an adventure game, but they should 
not be delivered in a bald style like:

`SUDDENLY A HUGE OGRE LEAPS OUT UPON YOU'.

Repeated events of this nature are no longer surprising nor even interesting 
if they are largely unrelated to the player's actions. 

If the huge ogre leaps out of a hat box the player has just opened, 
or the pond he has decided to swim turns out to be inhabited by man-eating 
ducks, then the player will start to anticipate surprises.

 For a build-up of tension, you need to establish that 
almost anything can happen if the player is careless, and then have 
a period of relative peace between incidents.

              Craft:

The craft of the adventure author lies in his use of image, sound 
and text. However cleverly designed, the game stands or falls by the 
craft applied to its development.

         Images:

Be careful when making your graphics for the game to make each image 
professional. Drawing a childish image just for the sake of having 
`graphics' can easily devalue an otherwise excellent piece of work. 
It is better not to provide an image at all than to provide an inferior 
or misleading one.

The recent advent of digitisers, which can take a picture and turn 
it into a screen image, has made it easier to produce good screen 
images, but again at a cost in storage.

*** This paragraph has been left in the dust of progress***
Remember, in any case, that some of your users will have low resolution 
graphics. To ensure a wide distribution, you must design to the lowest 
common denominator, which in the case of Spectrums, C64s, Amigas and 
STs is a TV set, and in the case of IBM PCs is a CGA-compatible laptop 
with LCD. In short, do not presume a high resolution. Design your 
picture so that it is balanced and well-proportioned. Then, even if 
it appears in shades of grey, it will still look good, especially 
from a distance. This does not prevent you from producing stunning 
graphics for the top-of-range computers, what it does is to widen 
your marketplace.

*** So has this one ***
Ideally, we would often like our graphics to be like Foss or Roger 
Dean paintings - in fact, like the cover of this book or an LP. Bear 
in mind, though, that these illustrators are dealing in detail at 
hundreds of dots per inch and three thousand shades of colour, while 
we computer artists are dealing in tens of dots per inch and tens 
(at best) of colours.

*** But these haven't! ***

 This is not a book on graphics, but here are some starting 
points for the beginner:

     Study perspective. So many promising computer graphics 
are spoiled by a lack of understanding of how objects diminish with 
distance, and parallel lines converge in perspective.

Get a book on artistic composition. There are two helpful outcomes 
of this. A well-composed picture is easy on the eye, and suggests 
an atmosphere much more readily than a cluttered one. In addition, 
a well-composed picture will tend to have large blank areas on it, 
which saves you work. Avoid fiercely symmetrical pictures, and ones 
which have the focus of attention in the centre, or which are divided 
in half by a horizontal.

Try not to fill the screen with the picture. You will save storage 
and produce a better effect if you frame a section of the screen and 
place the picture in that.

Study the masters. Walt Disney backgrounds and Chinese paintings are 
masterpieces of economy and composition. The recent spate of Kung-Fu 
arcade games has spawned a particularly fine series of oriental backgrounds 
for their zapping and kicking. Snow scenes are good, too. Christmas 
cards often display an admirable economy with a well-wrought atmosphere. 
Beardsley pictures are beautifully balanced, but you won't be able 
to match his line.

*** No longer strictly true.  Now that stunning colour graphics are the
norm, even on PCs, the problem of the stepped diagonal line has
largely disappeared, and graphics that rely on line drawing are
much less satisfactory that those that rely on subtle colour.***

Possibly best of all models to use are high quality comic books. They 
can suggest stunning scenery and events with great economy of detail 
and colour. Their resolution and pallette range is much closer to 
the one we must use.

*** Nor is this, though there are some execrable examples of poor
perspective in characters ***

 In arcade adventures, you will have to bear in mind 
the fact that your puppet will probably not vary in size as you move 
him around, so you have to make the playfield shallow from front to 
back and avoid natural perspective. In effect, you have a stage. Use 
the artificial perspective set designers employ. A study of set design 
will be rewarding in many respects. Don't clutter the stage with extraneous 
items. Make sure the entrances and exits are wide enough so that your 
actor can get through them easily. Make sure your scene changes are 
so slick that the player doesn't get bored.

The golden rule for all computer graphics is... keep it simple.

         Sound:

*** This section on sound preceded sound boards.  I still think
all games should be playable in silence if desired, however.***

While sound is an important feature of arcade games, in adventures 
it is often a needless distraction. An adventure game must not, in 
my opinion, be dependent on sound, and must allow the sound to be 
suppressed. Although they are largely an intellectual medium, some 
adventures are accompanied by a little tune that plays throughout 
the game. Luckily, the tune can usually be switched off before it 
drives the player insane.

Sound can also be used as an additional `warning' stimulus about the 
approach of danger. Sometimes a sound in the middle of an otherwise 
silent game gives an agreeable surprise, when, for example, a magician 
appears or a monster is killed.

Recently, in the more highly developed arcade adventures, synthesised 
voices have been used. Regrettably, too, the speech is often hard 
to comprehend.

In common with high quality graphics, recognisable speech and sound 
effects is very greedy of RAM and backing store and games with both 
typically require special or top-of-the-range hardware and many kilobytes 
of backing store to operate at an acceptable response level.

On the other hand, music and conventional beeps and grunts are relatively 
easy and relatively economical of computing resources.

              Text:

The use of language in adventures is not simply a matter of spilling 
your ideas onto the screen.

There is a duty upon any person who delivers words to the public to 
employ proper spelling, grammar, punctuation and construction. You 
may not be writing great literature, but like every wordsmith, you 
should have a dictionary and thesaurus to hand and be ready to use 
them in earnest.

A thesaurus is particularly useful in finding the right word to use 
in any context, to form lists of synonyms, and to find alternate names 
for similar objects so that the player does not have a problem distinguishing 
between them.

         Style:

In my own adventures, the player is usually addressed by the game 
in a very personal fashion thus:

`You are in a dimly-lit cavern. There is a dark entrance 
to the South, where you first entered this cave, and a flight of rough 
steps leading downwards to the North.

There is a heavy sword here.

Your faithful cat is by your side.'

The game delivers the view as it is seen by the character, and the 
items, if connected to the character, are so described.

Whenever the game reacts to player input, it does so as game author 
to player, sometimes, as in Hobbs, putting my words into the mouth 
of a constant and inseparable companion. The reaction to `ATTACK MAGICIAN' 
might be:

`You thrust the heavy sword at the advancing magician, 
but miss, due to overconfidence and bravado. Why not try again?'

 Sword and Sorcery exponents often prefer the present 
tense narrative form with implied prior knowledge of the environment, 
thus:

`Grey Paladin stands in the Ancient Hall of the Wierdmage. 
North lies the Terrible Staircase, South the Hall of Arch Conjurors.

The great sword Toadpricker invites his steel grip.

Mogg the Mouse-slayer stands by his side.'

Whenever the game reacts to player input, it does so in the narrative 
form again:

`Grey Paladin thrusts Toadpricker at Hrrdtczx the 
Parsoneater.'

The style does create a different atmosphere, appropriate to certain 
themes.

 The present tense is, of course, optional. The narrative 
can read like an historical epic instead.

         Output Text:

In text adventures, keep your descriptions brief and to the point. 
There are two reasons for this. In the first place, the player is 
not there to read a Sir Walter Scott novel, and may become bored if 
your descriptions are too fulsome and detailed. In the second place, 
the more features of the scene that you mention, the more likely the 
player is to use a word from your location description in his command, 
and become disappointed when that item is not actually there. 

In most successful adventures, a single location description seldom 
exceeds 300 characters.

Try to remember, when writing location descriptions, that unless the 
location is a `YOU ARE DEAD' type of location, the player may visit 
the location a number of times. Do not write the location description 
as it would appear if the player only visits it once. The description 
should fit for the first and subsequent occasions, and any exceptional 
text like `At last! You've found it' should be programmed to appear 
only the first time the location is visited.

The same applies to the short messages that signal item or character 
presence, such as `There is a sharp sword here'.

Detailed item and character descriptions, on the other hand, may need 
to be longer. As the player should not need to access the same description 
very often, it cannot become boring. 

It is often helpful to have both a description and a text for things 
that can be read. 

For example `There is a large notice here' has a description `The 
notice is four feet high and three feet wide' (perhaps to indicate 
it could be used to wrap something) and might have a text such as:

`NO TRESPASSING. TRESPASSERS WILL BE EATEN.'

         

         Input Text:

Most adventure game systems have reasonable parsers, able to separate 
the parts of a user's input, and deliver each part of a composite 
command separately.

It is important, however, that you make sure that synonyms for verbs 
and items are provided wherever possible. If you feel the need of 
an abbreviation, make sure the abbreviation is communicated to the 
player. He is not going to start guessing which words you have decided 
to abbreviate.

Try, too, not to lock a problem solution in on a particular phrasing. 
I remember one US offering which required the player to guess `CRAWL 
THRU THE HOLE'. 

`GO INTO THE HOLE', `ENTER HOLE' and `SOUTH' (the hole was the only 
Southward exit) did not work. 

Another pitfall concerns the way other characters are spoken to. 

The best format I have come across allows 

`ASK HAROLD ABOUT THE VAMPIRE' 

for information seeking. 

`TALK TO HAROLD ABOUT THE PARTY' 

enables information giving. 

`HAROLD, EAT THE PIE' 

issues an instruction to Harold. 

The worst was `"HAROLD, VAMPIRE'  as the only form of conversation 
(note the lone double quote!). There was no other way of communicating 
with characters. The results of such requests were usually even grimmer 
than the format required.

Very common verbs may be attached to function keys or icons. It may 
be possible to menu-select items. It is indeed surprising how few 
verbs are required to conduct even an elaborate game. They consist 
of:

     - all the standard game management verbs, such as 

HELP, INVENTORY, LOOK, EXAMINE, SAVE, RESTORE, SCORE, QUIT;

- all the direction verbs - ie 

N, S, E, W, NW, NE, SE, SW, UP, DOWN, ENTER and EXIT;

- all the common action verbs which appear in many adventures, including 


ATTACK, KILL, EAT, DRINK, OPEN, CLOSE, LOCK, UNLOCK, GET, DROP, PUT 
x IN y, PUSH, PULL, TURN, PLAY, ASK x ABOUT y, TELL (TALK TO) x ABOUT 
y, LIGHT, EXTINGUISH, GIVE x TO y, READ, FOLLOW. 

Even if these are not essential to the game, it is best to have sensible 
responses to a player's attempts to use them;

- action verbs particular to the current game - such as: 

SWIM, PAINT, RUB, TIE x TO y, UNTIE x, COOK, BUILD, BURN, CUT, CLEAN, 
USE, KISS.

Remember to synonym as many verbs as you can, so that the player does 
not himself have to resort to a thesaurus to guess the word you are 
expecting him to use. 

For CUT, it is reasonable to synonym:

SLICE, CHOP, SEVER, SLASH, SAW, SLIT and STAB.

              The Technology of Game-Writing Systems:

In this section, I will outline some of the basics of game writing 
systems. No matter which system you choose, you should have most of 
these facilities or their equivalents. Appendix A lists a number of 
packages currently available.

         What does a game-writing system do?

In general, you specify all locations, items, characters and special 
circumstances to the game-writing system, and the system produces 
a game.

In the case of some commercially available game-writing systems, an 
editor is built into the product, allowing you to test-run the adventure 
bit by bit as you put the data in.

Most of the time, however, the data for the game is prepared using 
an editor of your own choice, and the ASCII file is fed into a `compiler'. 
The output from the compiler together with some system routines/programs 
is the runnable adventure. This technique usually eases transfer of 
adventures between machines.

If this is your first foray into adventure-writing, it does not much 
matter which system you choose for your first game. The important 
thing is to get some experience with a usable system that runs on 
your hardware. 

*** I reckon AGT is now the best, and ADVSYS has not seen the light
of day since I wrote this***
Of the text-only systems, I favour AGT for ease of use and cross-machine 
compatibility. Use ADVSYS for extra power if you can handle object-oriented 
programming.

I have used GAC on the Commodore 64, and found it very good. Its graphic 
interface was usable, and it had some nice facilities. GAC's successor 
for the Atari ST - STAC - has a similar interface.

A product called The Quill, which also has a graphics capability, 
has been very popular in the Sinclair Spectrum sector of the market 
in the UK. I have not used it, but have been agreeably surprised by 
some of the products produced with it. Quill's successor is PAW - 
Professional Adventure Writer.

*** AGT no longer lacks graphics***
*** A new arcade adventure system - RAGS - is due out soon ***
At the `top' end for logic facilities and cross-machine compatibility, 
but lacking graphics, are AGT and ADVSYS, which feature virtually 
a programming language for their command handling structure. PAW, 
GAC and STAC all have a good instruction system, too. GAGS, which 
was the fore-runner of AGT, had virtually no instruction structure, 
but a good adventure could still be written with it.

At run-time, each game-writing system has a particular sequence in 
which it processes standard locations and items, performs location 
changes, and obeys instructions. These vary from system to system. 
Some systems require the writer to specify two sets of instructions, 
one set which must be executed before the player can input his command, 
and the other for processing after the command.

At run-time, game systems vary in the number and sophistication of 
standard responses they give to standard and error conditions, and 
how many standard command verbs they understand and act upon.

The system I wrote for the Atari 800 (not commercially available) 
was unique in that it read and interpreted the data file at run- time. 
Its main advantage was that I could include software routines in the 
data to deal with special situations, including moving graphics and 
elaborate sound.

 If you are a programmer, and decide to build your own 
adventure game system, I can recommend the approach of separate editor, 
compiler and runtime system. It is cleaner, and more economical in 
resources.

         What does the system require from the author?

All locations, items and characters (and their synonyms) are described 
and defined according to a set of criteria specified by the game-writing 
system. These definitions will be similar to those described in Chapter 
8.

If there are graphics, the graphics are either connected firmly to 
a location, or, more usually, there is a picture file so that multiple 
locations can use either the same graphic or different combinations 
of more than one graphic, and so that special instructions can invoke 
an image.

The set of synonyms for standard verbs is defined, together with a 
number of extra verbs that the game will recognise. The game writer 
supplies instructions to deal with these extra verbs.

The `special situation' instructions are then defined. This is where 
the greatest variation arises between systems. The instruction structure 
is used to define the game's behaviour in special circumstances. Some 
systems have virtually no instruction structure at all, embedding 
a few special cases in the location and item descriptions. Most have 
a system for testing conditions and taking action according to the 
result. It is most useful if the instruction system can `see' the 
player's input and the current situation, so that the game can react 
to the use of a particular verb/noun combination in a particular location.

Using the instructions composed by the author, the game will be able 
to recognise special situations and carry out the corresponding actions.

An independent set of messages, coupled to the instructions, is also 
prepared. Some systems feature a unified set of messages so that the 
writer can alter the system standard messages if desired.

It is important to keep track of your progress at this stage. I usually 
use an editor, such as BRIEF, which allows me to edit multiple files 
simultaneously. This also gives me the possibility of keeping a journal 
file with all the things I might forget, like the numbers of special 
variables and the numbers and names of locations and items. If I didn't 
have this facility in the editor, then the notebook would come in 
useful again!

         Getting your Adventure Working:

The previous section makes it look as though you just pour the ingredients 
in one end and get the result out of the other. Unfortunately, it 
isn't like that. At any rate, the result when you do so would not 
be the success you were striving for.

The usual procedure is to input some data, compile and test. Then, 
when that is working, input some more.

In order to speed up the testing process, it is usually possible to 
put temporary short cuts in the first location to skip to much later 
stages of the game. One or more of the NW, NE, SW, SE exits are usually 
available in an early location for this purpose. 

Alternatively, you may be able to alter the start location. Equally, 
you may find you have to temporarily re-locate some items so that 
latter stages of the game can be played.

As all programmers know, the surest way to cause a bug is to cure 
another bug. Be sure to regression-test every time you make an alteration 
to an adventure. In the last instance, this means playing it all through 
again. 

Remember, too, that the direct path through the adventure is not the 
only one. You have to walk down all the dead ends and do a few silly 
things, too. 

The more sophisticated game-writing systems offer more opportunities 
for making an error.

 Remember to read what your descriptions and messages 
say. Very often, it is obvious that the game-writer has never actually 
inspected his text for mis-spelled, missing and duplicated words. 
We often see what we expect to see, so run the files through a spelling 
checker if you have one or ask a friend who can spell to read through 
them if you haven't.

When testing the adventure, after you think you've taken all the bugs 
out of it, watch someone else play it, and note their behaviour in 
your book. The results will tell you lots about the quality of your 
game, and how to improve it. The alternative to writing it all down 
is to print a journal of the play session if the game permits it, 
though sometimes what the player says and the expression on his face 
whilst playing are a lot more significant than what he types!  

Children are excellent play-testers, and for the really awkward user, 
choose someone who never plays adventures or who dislikes them. And 
make sure to use someone who feels no obligation to be polite to you. 
Close relatives are therefore a good choice!

For the best results with arcade games, including arcade adventures, 
we videotape both the game and the player.

 Remember that a bug left in the game will not only torture 
your players, it will return to extract its vengeance from you.

 

               Chapter 7

               How to Publish and Copy-Protect your Game

              Publishing:

No-one REALLY sits down to write an adventure without hoping to see 
it played by as many people as possible. There are a number of ways 
of publishing it. You can advertise it in a games magazine and sell 
it direct, you can upload it to a bulletin board and allow it to be 
distributed free or as shareware, or you can offer it to a software 
publisher to advertise and distribute for you.

Each of these ideas has advantages and pitfalls. 

         Self-Publishing:

Doing your own publishing gives you the best profitability if the 
product is successful, but it is full of pitfalls for the inexperienced, 
and time-consuming to do the job properly.

One way is to upload your product to one or more bulletin boards for 
the computer-owning public to download by telephone. The documentation, 
also uploaded, requests the player to send you a contribution if he 
likes the game. This is called __shareware__. Shareware depends 
on trust between the supplier and the user, and there is a danger 
that some users will never send in their contribution. The considerable 
advantages are that your overheads are low and that you can find out 
how good your game-writing skills are, as a new shareware package 
often excites lots of comment on the networks.__

 In any event, you must ensure that you obtain the necessary 
licences from the owners of the game-writing system to distribute 
games developed using their system. Each product has a different policy. 


Some of the possibilities are:

     They grant the licence by virtue of you buying their 
system

They require that you submit a once-only payment and a copy of each 
game distributed

They request a small royalty if you sell more than 150 copies

They sell you a different version of the product for public distribution.

*** AGT is now Freeware ***
There will almost certainly be no possibility of the copyright owner 
allowing you to upload his software to a bulletin board, unless, like 
ADVSYS and AGT, the game-writing system is itself a shareware product.

Organise the packaging. This may be an expensive activity, especially 
if you want to copy-protect the game and make its packaging look attractive. 
Only if the product is not on public display, but sold exclusively 
by mail order, can you afford to skimp on packaging quality.

 When you are sure you have a complete and packaged product, 
arrange for an advertisement in a suitable magazine. You must expect 
any display entry, even a black and white one, to be expensive compared 
with classified small ads. You will find that regular advertising 
in a number of magazines is disproportionately more successful than 
a single entry.

         Using a Publisher:

A software publisher should take licencing, packaging, production, 
distribution, advertising and other worries off your shoulders. 

However, most large software publishers are surprisingly unwilling 
to distribute a game they haven't commissioned. There is pressure 
on them to justify the cost of full-page colour adverts. Wholesalers 
require big mark-ups on the selling price of games and the overheads 
of games publishers are so immense that they have to be fairly sure 
of selling thousands of copies of a product before they will market 
it.

This they ensure, most of the time, by picking up syndicated properties 
like Superman, Batman and James Bond and commissioning a game with 
a clear idea of what they want to see in it. Even then, they are burnt 
sufficiently frequently to make them extremely wary of any product 
that isn't a SURE FIRE WINNER and STATE-OF-THE-ART. 

Surprisingly, the games that sell well tend to be copies of existing 
best sellers and are often inferior in intellectual content. This 
pattern does not suit us adventure writers at all.

Smaller companies like Amazon Systems advertise on a less costly basis, 
and will advertise several titles in the same entry. While sales volumes 
are inevitably smaller, direct mail order cuts out the markup expected 
by retail outlets. There is, however, a limit to the number of titles 
such companies can market at any one time, though a specialist company 
of this sort may have a very good mailing list of potential adventure 
game customers.

 In summary, if you can persuade a publisher to distribute 
your product, that probably gives you the best long-term return on 
your investment of time and effort. Royalty levels for software run 
at a very low level, but remember that you can become rich on a small 
percentage of a winner!

              Copy Protection:

If you do sell an adventure, be prepared for it to be pirated if at 
all possible. How can you copy-protect it?

*** Nowadays, CD is a great security device if you can afford it!***
Hardware protection methods can be expensive, and may cost the distributor 
more sales than they save. Discs with indelible identifiers and dongles 
can be effective, but there's often some piece of `compatible' hardware 
that the system does not work with. Add to that the fact that amateur 
pirates have all the spare time in the world to work round the problem 
as an academic exercise, then they freely distribute their security-cracking 
system on bulletin boards, advertising it as a back-up feature, and 
that's the end of that. 

There is a growing movement against hardware-enforced copy-protected 
software from people who insist on their right to have a security 
copy of software, or who dislike mounting an unnecessary piece of 
hardware every time the game is run, and large software suppliers 
are tending to rely more on documentary and legal safeguards.

The principle to follow is to ensure that it is hardly worth the casual 
buyer's effort to pirate your work. To achieve this, your product 
must be cheap and easily obtainable. Many US adventures were pirated 
just because very few High Street traders stocked them and Mail Order 
distributors took forever to obtain them from the USA because they 
advertised without having them in stock.

         How, then, can your software be copy-protected?

An excellent protection for adventures is to supply a piece of printed 
matter or a product that is essential to the game or highly desirable 
but hard to reproduce.

 Desirable commodities include lavish colour illustrations 
of characters and items, maps and plans, posters that look good above 
the buyer's computer, badges, scorecards, models and plastic trinkets.

         How can printed matter or products be essential to 
the game?  

Well, for a start, they can contain the key to a code that has to 
be cracked in the adventure. It may be a map, or it can contain essential 
information to answer a question. A good place to put such questions 
is before a SAVE file can be RESTORED. This means the adventure can 
be played, but probably cannot be won without the information.

It is helpful if the fact that the game needs the enclosures is hidden 
until the player has gone some way into the game. People often take 
a pirate copy of something because they want to see what it's like 
before buying. If the game hooks them and it's inexpensive, they buy 
their own copy.

         How do you make printed matter hard to reproduce 
in these days of photocopiers?  

There are three ways:

     It can be big in terms of pages or in format

It can be in colour or transparent

It can be on the original disc or cassette.

A big insert can be a booklet. Some commercial products have a booklet 
with many pages which are hard to photocopy - they are small, and 
embarrassing to be found doing in the office!  The only purpose of 
the booklet is that the player is going to have to use it to crack 
a code or is going to have to reply to questions like: What is the 
third word on the sixth line of page seventeen in the book? 

Alternatively, the booklet may be intrinsically desirable, and contain 
essential details of characters and equipment featured in the game. 


Another ruse is to print the insert at A2 or A1 size, so that it cannot 
be readily photocopied. No-one really likes using something that is 
stuck together with sellotape. If you print an apparently insignificant 
number at the foot of a legal size (or foolscap) sheet, the pirate 
may omit to copy the number when taking an A4 photocopy. A serial 
number printed on the game box may be missed during a photocopying 
session, too.

**** Groan... until the advent of cheap colour scanners, that is.***
A coloured insert of large size is an excellent idea, because colour 
photocopying costs about 15 times as much as monochrome. Most pirates 
find this an even bigger turn-off than sellotape! From your point 
of view, however, colour printing is very expensive - much more than 
four times the cost of monochrome, especially for print runs of less 
than 1000.

One of the elaborate forms of colour printing is red-green 3-dimensional 
pictures. There are also other forms of 3-D printing including a process 
for producing hologram-like pictures, which would be impossible to 
copy cheaply.

To make colour printing worth your while, it must have either beauty 
in itself, or importance to the game. In these circumstances the would-be 
player may find it worthwhile to buy your game rather than steal it. 
The down side of colour documentation for copy protection is that 
colour-blind players may be at a disadvantage.

Though it is possible to photocopy onto transparent sheets, it is 
again more the province of the professional office, and difficult 
to do casually or cheaply. Such a sheet could form part of a code-breaking 
or password identification system, particularly if it combined colour 
with transparency.

Just in case you were thinking of trying it, never put a floppy disc 
in a photocopier. There's a good chance you will damage the data on 
it. For that reason, and because no-one looks closely at disc labels, 
it's a good security idea to print some essential data on the label 
of the original disc. We did that with the Paul Daniels Magic Adventure, 
and some pirates even had the cheek to 'phone us up to find out what 
the information was!

One game publishing firm hit upon a good idea. They had a habit of 
filling their packages with various trinkets and pieces of paper. 
For example, one product was sold as a dossier in a colourful folder 
filled with sheets of paper of different and odd sizes and colours, 
and with photographs and other items. It was not obvious which one 
was going to be important for copy protection, so the potential pirate 
had to copy them all, with the result that it became unattractive 
to make a copy for someone else.

Three more ideas that come to mind are:

     codewheel - a sort of circular ready-reckoner with 
multiple discs which are a bother to reproduce

scytale - a combination of a printed item and a cylinder of a certain 
size. The paper is wrapped around the cylinder to reveal one or more 
secret messages

security lens - an optical device which must be placed over a small 
section of the screen to decipher a codeword.

 Copy protection is a tricky subject and can even have 
a damaging effect on overall sales. Therefore, make sure your protection 
is either entertaining or at least trouble-free for the bona-fide 
user. 

              Cheat Protection

A subject allied to copy protection is cheat protection. Many of the 
early adventures could be solved by running the game's data file through 
an editor program and reading the messages. Even though the instructions 
could not be readily comprehended, the messages could give away the 
secret of how to do something. 

Typically, a message might read:

As you put the coin in the slot, you hear a click.

which is pretty revealing.

The way to prevent this happening is for the game-writing system to 
encipher the data files before distribution, and decipher the data 
in the messages just before displaying it. 

Even then, smart users are going to be able to decipher them. This 
they tend to do, not by being cipher experts, though many of them 
undoubtedly are, but by tracing the code that the game-writing system 
uses to decipher the messages. This is a laborious process that most 
of us programmers hate, but which will eventually reveal the cipher 
algorithm.

Having found out the method, they apply the same algorithm to the 
data files and reveal the messages for themselves.

One such system to `crack' the encipherment used by one major games 
company was launched onto the world's public  bulletin boards some 
years ago, though the victim company quickly dealt with the problem.

 You must assume that a small percentage of your users 
will take the trouble to peek at your messages. Even those few game-writing 
systems which do provide encipherment may still unlock your secrets 
to an owner of the game-writing system you use. So try to conceal 
the important messages in the game, and, in particular, the questions 
and responses you use for copy protection.

One method to employ is:

     Don't be explicit with your messages. Instead of 
saying:

         As you push the button, the tiger leaps out.

     say:

         What a surprise! The tiger leaps out.

     so you haven't revealed why the tiger appeared. The 
legitimate player knows he pressed the button just beforehand.

Alternatively,

     Don't put the whole message in one place. In the 
previous example, you might make two messages as follows:

         As you push the button,

     and 

         the tiger leaps out.

     And display them separately, one after the other. 
Of course, these messages mustn't be stored next to one another on 
the data file.

Or even,

     Some game writing systems allow the game writer to 
store the messages like this:

         As you =VERB= the =NOUN=, the =ITEM23= leaps out.

     and the PUSH and BUTTON from the player's command 
and the game's item 23 (tiger) are only filled in at run time.

  

 



               Chapter 8

               The Architecture of Adventure Games

This chapter describes in more detail  the components which make up 
an adventure game.  The principal entities being:

     __Locations__ (or __Scenes__ or __Rooms__)

__Items__ (or __Objects__ or __Nouns__) which populate these 
Locations

and

__Characters__ (__People__,__ Creatures__, __Monsters__ etc.) 
which roam the Locations.  

The player interacts with the game by means of:

__Commands__, which he types into the computer. Commands are based 
around the syntax of the English sentence.  Foreign language variants 
may require the verb or adjective to be in a different position, both 
in Command input and in responses.  Even where a graphic adventure 
requires the user to point at icons, these icons represent 'parts 
of speech'.

__Messages__ are displayed by the game. Some messages are associated 
with the standard locations and items, while others are displayed 
in response to player instructions.

__Instructions__ are included in the game by the writer in order 
to deal with special situations like transformations and discovery.

 Instructions have a number of data items available to 
them. These are: __Variables__, __Flags__ and __Counters__.

              Locations

The features of a Location - also known as its __Attributes__ can 
be:

     __Location Number (or Identifier)__: a unique identifier 
for the Location. It may be the same as Short Description in some 
adventures, though it is often useful to be able to have the same 
short description for two Locations which are logically different

__Short Description:__ used as a shorthand 'heading'  for the Location

__Long Description:__ in text adventures a verbal description, in 
graphics adventures a picture or scene, perhaps accompanied by a verbal 
description

__Exits:__ a list of Locations associated with standard directions 
from current Location. 
eg DOWN - Cellar, UP - Loft

__Light:__ whether the Location is intrinsically lit, or whether 
a light source is required to illuminate the scene.  Sometimes, only 
a particular type of light source would be valid in this particular 
Location

__Reward:__ usually implicitly 0, but may be a number of points 
awarded for successful arrival at current Location

__Help:__ in some game-writing systems, each Location is permitted 
a piece of text which can be offered as a hint if the player commands 
HELP (in other cases, a HELP command is associated with some other 
type of status, not the current Location)

__Status__: usually implicitly Normal but could signal that this 
is Start Location, Untimely End Location, Resurrect/Restart Location, 
Game Won Location, Treasure Room - ie Location in which points are 
scored for leaving Items

     __Bounce:__ in some game-writing systems, a Location 
is permitted to be a 'bounce' Location.  ie if the player enters this 
Location, it is described, but the player is thereafter returned to 
the Location he came from

__Special Commands and/or Items:__ commands or items which have 
a special significance in the current Location, but not in others 
- for example, if the Location were at a riverbank, then the command 
NORTH might have the special meaning SWIM at this Location

  

              Items

The Attributes of Items can include:

     __Item Identifier__: Number or other unique identifier 
of Item

__Item Name__: a word, such as WALLET, which is used as the principal 
identifier for this Item in commands

__Synonyms:__ other words which are also valid for identifying the 
Item, such as PURSE or BILLFOLD

__Adjective (or adjectival phrase):__ to distinguish this Item eg 
BROWN LEATHER

__Short Description:__ for use when describing the Item in a Location.  Typically, 
this short description would be `There is a brown leather wallet here'

__Situation:__ where currently located - could be inside another 
Item, in the possession of a Character or could simply be in a Location 
or Limbo

__Detailed Description:__ a complete description which will be delivered 
when the player commands EXAMINE or INSPECT Item

     __Text:__ often an Item such as a book or a note 
has both a description and a text.  The text can be activated by READ 
Item

__Singular/Plural:__ in order to make the grammar of game responses 
correct (although a distressing number of games give responses like: 
`the jewels __is__ not here.'!)

__Fixed/Movable:__ refers to whether Characters can GET it.  Associated 
attributes Size and Weight may also apply


     
__On/Off:__ used for a variety of purposes.  For lights, whether 
lit, for magic wands, whether energised, for containers whether empty 
etc

__Light__: whether it gives out light if also ON

__Open:__ for containers/doors whether open or shut

__Locked:__ {for containers or doors) whether locked or unlocked.  Associated 
attribute would be the Item number of the key to unlock it

__Points:__ how many points the Item is worth, either as an immediate 
bonus, or when delivered to a Treasure Location

A raft of other attributes are possible, depending on the game or 
the game-writing system and can include:

     __Weapon:__ Yes/No and Weapon power

__Food:__ Yes/No and whether poisonous

__Garment/Armour:__ Yes/No and Armour Class as in Dungeons & Dragons

__Cost:__ How much money required to purchase

__Magic Spell:__ Yes/No and Type

  

              Characters

Some game-writing systems make no qualitative distinction between 
Items and Characters. Others differentiate between Monsters and Friendly 
characters, or between Humanoid and Animal or Creature.  These distinctions 
can help or hinder the game writer to some degree, but are otherwise 
unimportant.

The Attributes of Characters can be drawn from:

     __Character Identifier:__ Unique number or other 
identifier

__Character Name:__ a word, such as THIEF, which is used as the 
principal identifier of the Character in commands

__Synonyms:__ other words or proper names which are also valid for 
identifying the Character, such as CUTPURSE or FAGIN

__Adjective (or adjectival phrase):__ to distinguish this Character 
from other Characters of the same general type eg LEAN AND HUNGRY

__Short Description:__ for use when describing a Location.  Typically, 
this short description would be `There is a lean and hungry thief 
here' or `Fagin is here'

__Situation:__ where currently located - for example in a Location 
or Limbo, or could be inside an Item, such as a wardrobe

__Detailed Description:__ a complete description which will be delivered 
when the player commands EXAMINE or INSPECT Character

__Singular/Plural:__ for correct grammar in game responses when 
the Character is multiple.
eg IS/ARE and IT ITS/THEY THEM THEIR

     __Gender:__ ie for correct use in game responses 
of HE SHE HIM HER HIS IT and ITS 

__Friendly/Hostile:__ to deal with types of response to speaking 
with or attacking the creature.  Other attributes describing the degree 
of ferocity, strength, vulnerability etc

__D & D characteristics:__ Class, Courage, Wisdom, Constitution, 
Dexterity etc

__`Achilles Heel'__: Weapon to which the character is particularly 
vulnerable. eg fresh air, exercise

__Points:__ for meeting or defeating creatures

__Companion:__ Yes/No - Yes means the Creature tries to follow the 
player Character from Location to Location.

  

              Commands

The simplest command usually accepted consists only of a verb.

Typical free-standing verbs are:
HELP, LOOK, INVENTORY.
Most adventures also accept direction `verbs' such as: NORTH, SOUTH, 
EAST, WEST.

An important pair of special verbs is:  
SAVE and RESTORE
which allow the player to dump the current state of the game and reload 
it later.

Conventionally, the one-word verbs:
SCRIPT and UNSCRIPT
are used to switch a printed journal of the game on and off.

The next stage of command construction is: Verb Noun.  Examples are:
OPEN BOX
CLOSE DOOR
and GET APPLE.

Most games allow for and ignore:
THE, THIS, A, AN, MY, HIS before a noun.

So the above examples could have read:
OPEN THIS BOX
CLOSE THE DOOR
GET AN APPLE.

A Noun may be an Item or a Character.

If there may be more than one of a noun, for example a red box and 
a blue box, it should be possible to distinguish these.  For that 
reason, it is usually permissible to have an adjective with any noun, 
so that OPEN RED BOX is understandable to the system, even if there 
is no other box to be referred to.

Another common construct allowed is to pass the command to another 
character in the story, thus:
WIZARD, ENCHANT THE PRINCE.

Some actions cannot be expressed in this way, even by sticking multiple 
Verb Noun commands together.  These are of the form:
UNLOCK THE DOOR WITH THE KEY
HIT THE BALL WITH MY CLUB
ASK THE MERCHANT ABOUT THE GOLD.
In these commands, a preposition is permitted before the second noun.

The next important construct is the chaining of commands together, 
as, for example:
EAT THE EGG THEN DRINK THE WINE
GET THE DUCK AND SHOOT THE GOOSE.
The game will usually treat these as two separate commands.  Even 
OPEN BOX, EXAMINE BOX are acceptable to many games, substituting a 
comma for the conjunctions THEN or AND.

It is often permissible to supply multiple nouns as in:
PUT THE BOTTLE AND THE BAG IN THE BASKET, or GET BUCKET, SPADE.

There are a number of strategies for reducing input for text adventures.  One 
of these is to reduce common verbs to a single letter as in H for 
help or I for Inventory.  Another is to allow AGAIN or G as an instruction 
to repeat the previous command, so that, for example, if you are fighting 
a troll, the player could just say HIT TROLL WITH STICK once, and 
repeat G until the troll begged for mercy.

Another common solution is to allow IT or HIM or THEM as a substitute 
for the Noun used in the previous sentence, as in:
FOLLOW THE PRIEST, TALK TO HIM
or GET THE APPLE AND EAT IT.

The collective Noun ALL and its exception ALL BUT are also commonly 
allowed in games.  For example, GET ALL would typically transfer to 
the player's inventory all the movable Items in a Location, while 
DROP ALL BUT SWORD would drop everything the player was carrying, 
except the sword.

              Messages

The messages in a game are the main area of communication between 
the game and the player. They are displayed by the game system itself 
to signal standard situations. The game writer can also trigger the 
output of messages as a response to player input. 

Often, the game writer has the option to change even those messages 
that the game system outputs. In this way, a game can be considerably 
customised.

              Instructions

Game-writing systems show great variance in the area of Instructions.

The game writer uses the Instructions to monitor the game and to handle 
all the player actions the game-writing system cannot handle.

For example, most of the game-writing systems will move the player 
successfully from Location to Location, by simply recognising the 
direction commands input by the player and reacting appropriately. 
Most will also handle GET, DROP, OPEN, CLOSE and so on.

 However, you will want additional control. For example, 
you need a mechanism for opening secret exits if the player acts in 
a certain way. You may want to set a timer to catch the player in 
an ambush. You will need to move your non-player characters around, 
do transformations and discoveries and react to non-standard commands 
like PEEL THE BANANA.

__Conditional__ Instructions are used by the game writer to test 
for conditions that the game knows about.

__Action__ Instructions actually change the state of the game in 
some way.

__Control__ Instructions handle the sequence in which the game instructions 
are obeyed.

This is hard to communicate, so let's take a typical example. Suppose 
we are dealing with teleporting the player to the palace if he drinks 
a potion, but only if he drinks it in the torture chamber after midnight. 


I will use AGT's instructions as an example.

Each set of instructions is grouped under a COMMAND that the player 
has input, so the sequence would go:

COMMAND DRINK POTION
IsCarrying 221  (Player carrying flask?) conditional
AtLocation 18 (In Torture Chamber?) conditional
FlagON 2 (After midnight?) conditional
GoToRoom 88 (go to the palace) action
SwapLocations 221 222 (Switch the full flask for an empty one) action 
DoneWithTurn (Don't process any more instructions) control END_COMMAND

and the instructions to deal with failure are:

COMMAND DRINK POTION
IsCarrying 221  (Player carrying flask?) conditional
SwapLocations 221 222 (Switch the full flask for an empty one) action 
PrintMessage 125 (`Sorry. You got it wrong.') action
DoneWithTurn
END_COMMAND

 

              Variables, Flags and Counters

Not all game-writing systems provide all three types of data. Luckily, 
a variable can be used to substitute for either of the other types.

Variables are used by the game to store numbers. We might use variable 
1 to keep note of the number of gold pieces the player has. Then if 
we need to display a message showing the value of the player's purse, 
it might be:

You have =VAR 1= gold pieces

and the system would substitute the number of gold pieces for =VAR 
1= when it was displayed.

If the player were trying to buy a new sword, we could cause the instructions 
to check variable 1 to make sure he could afford it.

Flags are used to remember ON/OFF switches. A flag is either on or 
off. A Flag might be used in the game to indicate whether the player 
had met a particular character on some previous occasion, in order 
to suppress the initial encounter message at later meetings.

Counters are variables which the game itself increases or decreases 
by 1 at every turn. They are used to schedule all sorts of time-dependent 
events.

Instructions usually exist to compare and calculate with the various 
counters and variables. Other instructions can be used to set and 
clear Flags, and to test their condition. 



               Chapter 9

               A Text Adventure
Example

Here is an epic fragment of one of my own text adventures, 
written using Softworks' AGT game-writing system. 

You will know where you are by reading the short description 
between the <<>> signs.

The game prompt is `What Now?'
The player command is in upper case.   

Sir Ramic Hobbs and the High Level Gorilla
                by Gil Williamson
                1st December 1989

                     Introduction......

Just in case you've forgotten,  you are Sir Ramic Hobbs,  Knight  Errant.  It 
really WAS an error to come out on this Quest.

I am your guide.  My name is Prang,  Wizard Prang.  I'll try  to  keep 
you up-to-date with what's going on by means of disembodied  voice, 

a technique I learned from the Flying Sorceror, Ufo Snafu.  I once 
had a body, just like yours... well, not JUST like yours..  until I offended 
Sir Kewler Stairs, who disembodied me with  one   blow of his handy 
mace.  Still, I make myself useful.

<< Smelly Cave >>  
You are in an extremely smelly cave.   The floor slopes  steeply from 
West down to East. There is a faint glow from below, whence the 
smell appears to be emanating, and a rather  brighter  light from 
above.  The floor is slippery. 
    There is an ornate sword here. 
    There is a round peg here.
    There's a signed agreement here.
    There is a curious flute here.
    There's a grubby manual here.
    There is a rather untidy owl here.
    ============

What Now? INVENTORY
You aren't carrying anything.
You are wearing the following:
  steel helmet 
  suit of armour

What Now? EXAMINE HELMET AND SUIT               
You 
are wearing a battered steel helmet with a ragged plume on top, and 
a visor that opens and closes. There's not much of you visible. You 
are completely encased in a rather rusty suit of armour handed down 
from your uncle, who perished in it.  You can still smell him.    

What Now? EXAMINE SWORD      The  sword 
looks valuable,  but I wouldn't try hitting a  bear with it, 
if I were you.   Take my advice. A person in your condition should 
NEVER take on a bear under ANY circumstances.  Oh, and by the way, 
the sword is blunt.  

What Now? EXAMINE AGREEMENT      It's 
an agreement you rashly signed whilst under the influence   of 
mead at the Khan's Pleasure Dome Night.  It's worth a read, actually.

What Now? READ AGREEMENT      
It reads:    "__AN  AGREEMENT  MADE IN THE KINGDOM,  OR PERHAPS THE
KHANDOM,  OF TRASCH KHAN, WORTHY SUCCESSOR TO CUDDLY KHAN, BUILDER OF 
THE DOME, ON OCTEMBER THE 32nd.__
    "__BEING OF SOUND MIND__ {That's a laugh! after all that mead!}
__I, SIR RAMIC HOBBS __{That's you, remember}  __AGREE TO RETRIEVE 
PRINCESS ANNE DE PEA FROM THE EVIL GRASP OF THE HIGH LEVEL GORILLA 
__{That's HLG,a formidable chap who could, with two fingers, compress 
your windpipe till all you could wheeze was 'eek'}, __NOW RESIDENT 
AT THE TOP OF THE MIDDEN.__
   "__SIGNED,   SIR RAMIC HOBBS__" ... that's it.
You woke up in a cave about half-way up the Midden, with your mead  supply 
expired.  Bad news.  You were meant to bring a ransom,  but  you 
left it behind,  so back to the Dome with you!  Sorry!  

What Now? EXAMINE FLUTE      
It looks clean (as a whistle, Ho, Ho). Can you play?  There's 
something written on it.   

What Now? READ IT      
In tiny writing, too small for your bloodshot eye to read, it says: "With 
the compliments of the Arabian Knights' Company."     

What Now? HELP      
Perhaps you should consider leaving this hell-hole. 

What Now? GET PEG    
You are now carrying the round peg.

What Now? E
<< Bear Lair (West) >> 
This is where the smell was coming from,  all right.   There are piles 
of it on the floor.   The inhabitant of this cave doesn't do it 
in the woods.   The cave where you woke up is to the West. 
The main part of the Bear Lair is East of here.
   There is a round hole in the wall at shoulder height.
   ============

What Now? EXAMINE HOLE
There is some mechanism inside the hole. 

What Now? PUT PEG IN HOLE AND PUSH IT   
You have put the peg in the hole.     
The peg cleverly resists your touch.

What Now? PULL IT     
There seems to be a bear moving around in the bear lair.     
Pulling on the peg doesn't seem to work.

What Now? HELP
None of us are enjoying this very much.  There must be something sensible 
to do.    

What Now? TURN THE PEG

Turn, turn, turn...     



What Now? W 
<< Smelly Cave >> 
You are in an extremely smelly cave.   The floor slopes  steeply from 
West down to East. There is a faint glow from below, whence the 
smell appears to be emanating, and a rather brighter light from 
above.  The floor is slippery.
  There is an ornate sword here. 
  There's a signed agreement here. 
  There is a curious flute here. 
  There's a grubby manual here.
  There is a rather untidy owl here.
  ============

What Now? W
<< Precipitous Ledge >> 
You are standing on a precipitous ledge above what is called 'an aching 
void'.  You're not quite sure whether the void aches more than 
your head.   A long way below,  to the West,  you can see a castle  on 
the shore of the Sunless Sea, which stretches off  to the 
South.   Round to your left,  far below,  at the foot of the Midden, 
the River Alf steams (yes, steams) into the sea.  Behind you, 
to the East, is a cave.   A path sneaks North, through some bushes.
   There's a wooden fence in front of you. 
   There is a rather untidy owl here.
   ============

What Now? EXAMINE FENCE      
The fence is fairly sturdy - sturdier than you - but not securely fastened 
in place.      

What Now? EXAMINE OWL      
The owl is extremely dirty and threadbare.  Bloodcurdling Owl is his 
name, but we'd better call him BO for short.     
BO :__ Eminences, my disgusting name is Bloodcurdling Owl. Because
    this is needlessly long, honoured beings may call me BO for 
 short ....__   
Yes, I've just told him all that.  Sir Ramic is not deaf, merely hungover, 
as serves him damned well right.     
BO :__ I beg your Graces' pardons.   If Sir Ramic is so foolish as
    to require my advice, let him say: ASK BO ABOUT whatever.
    Now allow me to remove my unpleasant presence to a discreet
    distance.__   

What Now? ASK BO ABOUT FENCE      
BO : __If your eminence is prepared to take the advice of one
    who has but recently crawled from under a heavy stone,
    only an ignoramus like myself would need to ask  about
    that. __

What Now? ASK BO ABOUT QUEST      
BO :__ I grovel at your feet, Highness. I have heard them say
    this  quest is characterised by a total lack of  importance.
    Like me, and unlike you, the items and characters populating
    the  halls of this world are only there because they have to
    be, and would much rather be left to their fates.__ 

What Now? ASK BO ABOUT ANNE      
BO :__ My stupefyingly ill-considered  feeling is as follows:
    one has frequently seen better turned legs on a sideboard,
    her voice is clearly audible over a circular saw, but she is acutely
    sensitive on the subject of eating in bed. __     

What Now? EXAMINE BUSHES
You see nothing unusual.

What Now? N 
<< Vantage Point >> 
From this high and windy vantage point, you can see miles to the North   and  West.   To 
the North,  the Khan's pleasure dome  is  occasionally   visible  through 
squalls of rain,  beyond forests ancient as the hills   (it 
says here).
Far below and to one side, you can see a ledge with a grove of bamboo.
To the West, Baron Doar's castle guards the only road to the  pleasure   dome.
What a pity you're going to have to walk all that distance, Sir Ramic..  .. 
if you ever get down from this rock, that is.
A narrow path goes South, through some bushes.   There are some  steps 
leading upwards.    ============

What Now? HELP      
Relax. The fresh air here will do you good.   

What Now? RELAX
I don't understand RELAX as a verb.

What Now? WAIT    
Time passes...

What Now? UPWARDS 
<< Tunnel Entrance >> 
You are at the entrance to what has once been a mine. Rails lead East  into 
the tunnel.   The only other way is back down to  the vantage 
point.   ============

What Now? HELP      
For God's sake, cut out the snivelling, Sir Ramic.  

What Now? E
<< Tunnel >>  
You are in the tunnel. There is a light at the end of the tunnel.   With 
your luck,  it's an oncoming train!   Just East of you here,   there is 
a gap in the tunnel floor,  though the  rails  continue 
across  the gap.   Water cascades from the ceiling into this gap, 
and disappears with a loud roar.
The gap is too wide to jump across, and the rails look slippery.
 There is a strange-looking bat here. 
 ============

What Now? EXAMINE BAT      
The bat is about thirty inches in length, consisting of a round  handle 
of about ten inches, and twenty inches of flat blade.  It 
is, in fact, a CRICKET BAT, and an Englishman like you, 
Sir Ramic, will find many ways to USE it.    

What Now? GET BAT THEN USE IT    
You are now carrying the strange-looking bat.    
You play with the bat for a while. Nothing significant happens.

What Now? EXAMINE GAP      
You see nothing special.   

What Now? EXAMINE ROCKS
You see nothing unusual.

What Now? HELP
What you need here is something to bridge that gap. 

What Now? E 
<< Cascade >>  
You were WARNED, Sir Ramic. 
As predicted, you miss your footing.  Not at all surprising, really.     The 
cascade plunges 40 feet onto a stone slab.  You cascade with it.     As 
well as getting extremely wet...
**** You are Dead ****      ============ 

You have seen 7 locations (out of 69), in 38 turns. 
Your score is 0 out of a possible 163 points. 
(This game was saved 0 times and restored 0 times.) 

In a graphics adventure, these locations would have been 
illustrated by a picture, with or without accompanying text.

The commands such as INVENTORY, EXAMINE, NORTH would have 
been input by icon and item select.

  







               Appendix A

               Some Game-Writing Systems


**** The data in this appendix is out of date.  Consult Computer
magazines and BBSs for up-to-date info.***

            Appendix B

               Some Games the Author has Played, Seen or simply
Discussed. 

My apologies for having missed many adventure games, particularly 
those issued on only one or two machine types, but this appendix concerns 
games about which I have actual knowledge.

The publishers are listed in the sequence in which I first became 
aware of their games. This has resulted in them appearing in approximately 
chronological order of entry to the adventure market.

              Adventure International.

The Scott Adams text adventures were the first computer adventures 
I ever saw, and are still excellent examples of the genre.

They appeared on Tandy TRS80s before I saw them on an Atari 800.

     Pirate Adventure
Secret Mission       (previously Mission Impossible)

  

              Infocom Inc.

Infocom games were nearly all text-only until recently. The term __Infocom-like__ 
is often used to describe the classic game interface used in text 
adventures, and many of these games have become the models for the 
rest of the industry.

         Zork series:

     Zork I, II, III
Beyond Zork
Zork Zero

         Detective:

     Deadline
Witness

         Science Fiction:

     Starcross
Planetfall
Stationfall
Suspended
Hitchhiker's Guide to the Galaxy
Leather Goddesses of Phobos

         Fantasy & Horror:

     Wishbringer
Enchanter
Lurking Horror

         Other:

     Hollywood Hijinx
Bureaucracy
Shogun (with still graphics!)

     

              Magnetic Scrolls

A British firm who maintained (some say improved upon) the Infocom-like 
text interface and provided excellent still graphics, too.

     The Pawn

              Level 9

Another British firm which has brought nice graphics to traditional 
text adventures.

     Jewels of Darkness (Colossal Cave clone)
Gnome Ranger
Ingrid's Back

              Melbourne House

An Australian firm, again producing well illustrated text adventures.

     The Hobbit
Sherlock

              Sierra On-line Inc.

This firm has produced some of the most successful arcade adventures.

     Space Quest
Police Quest
the Leisure Suit Larry series

              Palace/Delphine

French-based adventure writers producing intricate arcade adventures.

     Future Wars

            Appendix C

               Bibliography

Just a few of the books you may find useful, in the form:

Title - Author (if available) - Publisher.

__Science Fiction Puzzle Tales - Martin Gardner -
 Penguin__
__A feast of thought-provoking puzzles for the mentally alert.

__Codes & Ciphers - Martin Gardner - Dover__
A small, but excellent manual on everyday codes and ciphers, as opposed 
to the kind used for computer and defence security. 

__The Dungeons and Dragons Handbooks -   - TSR Inc__  
__Study the art of the Dungeon Master. The adventure game writer 
is in a similar trade.__

__The Art of Walt Disney - Christopher Finch - Abrams__ is a super 
source-book for background technique. My copy is luxurious, but I 
believe there is a cheaper edition now.

__Chinese Brush Painting - Jane Evans - Collins__
Some instructive examples in economy of line and colour.

Comic Books by, for example, Frank Miller and Alan Moore demonstrate 
economy of background and excellent action.

 Anthologies of Poetry and Books of Quotations also often 
trigger inspiration.__

__De Re Atari - Chris Crawford - Atari __
Some of the essentials of good game creation were first formulated 
in this book on the Atari 800 home computer, from one of the most 
innovative computer games writers.

De Re Atari may be hard to find these days, but Chris has written 
another book - The Art of Computer Game Design - and is the editor 
of the Journal of Computer Game Design.

May I just remind you about:
__Roget's Thesaurus -   - Penguin__
The source of good synonyms. There are also computer-based thesaurus 
products nowadays, but I prefer a good browse through the paper version.

Finally, the__ Writers' and Artists' Yearbook -   - Black.__ Lots 
of sensible stuff about copyright, libel and royalties.

            Appendix D

               Checklists

              Checklist 1 - Major Stages in Adventure Game Development

     Decide on your Objective - Leisure or Profit
Choose a Game-writing System
Choose a Theme
Sketch out a Plot
Draw a Map
Design some Locations
Design some Items
Design some Characters
Assemble the Main Plot
Develop and Test
Play Test
Copy Protect
Cheat Protect
Package
Distribute.

  

              Checklist 2 - Some Background Themes:

         General:

     Crisis Management:
    Bank Robbery
    Mine Disaster
    Plague
    Flood
    Hurricane
Voyage under Sail
Mountaineering
Polar Exploration
Japan in the days of Samurai
Locked in the Asylum
Gangbusters
Biggles
Spycatching
Cave diving
U-boat 
Amnesia
Wild West

         Science Fiction:

     Time Machine
I, Robot (using Asimov's Laws)
Bodysnatchers (parasitic aliens)
Peace Enforcement at the Galactic Rim
Spying and Sabotage on an Alien Planet
Marooned in Space (or on a planet)
Post-holocaust
Encyclopaedia Galactica
Crime and Espionage on a Computer Network

  

         Fantasy:

     Journey beyond the Dawn
Ghostbusting (sorry - exorcism)
The World of:
    Egyptian Myth
    Indian (Red, South American or East) Myth
    Greek/Roman Myth or History
    Kalevala & other Norsery
Conquer Evil in the Land as:
    King
    Chief Wizard
    Army Commander
    Long Lost Heir
    Frog who once was Prince

         Non-traditional Uses of Game-writing Systems:

     I Ching (Chinese oracle)
Astrology
Troubleshooting
Programmed Learning

  

              Checklist 3 - Plot Elements:

Possession of Equipment
Collect & Assemble
Transformation
Discovery
Weapons
Apparel (Clothing/Armour)
Puzzles
Bribery
Logical & Geographical Mazes
Variable Geography
One Way & Restricted Exits
Secret Exits
Door Openers
Curtains & Carpets
Knowledge
Elaborate Patterns of Behaviour
Richness of Methods
Riddles
Transportation
Death & Resurrection
Containers
Push, Pull, Turn & Play
Food & Drink
The Senses
Invisibility
Following
Proxy Actions
Codes & Ciphers
Time Dependence
Weather
Clues
Logical & Physical Traps
Alarms & Ambushes
Unusual Uses
Skills, Powers & Magic Spells
Helping Out
Darkness, Obscurity and Illusion
Lies and Contradictions
Companionship
Monsters

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Date this article was posted to GameDev.net: 7/16/1999
(Note that this date does not necessarily correspond to the date the article was written)

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