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Andrew Rollings and Ernest Adams on Game Design Chapter 7: Gameplay


Applied Challenges

You will recall from Chapter 2 that gameplay consists of the challenges the player faces, plus the actions she can take to overcome them. As we said previously, designing the gameplay is one of your most important design tasks. To some extent, the nature of the challenge suggests the nature of the player's response. The best games, however, allow the player to think creatively and use unconventional actions to meet the challenges. At the concept stage, you don't have to define precisely what challenges the player will face, but it's good to have an idea of what kinds of challenges you want in the game. Applied challenges are the application and use of the pure challenge forms we have discussed thus far. An applied challenge is a combination of one or more pure challenge forms applied to a given gameplay situation or style.

Races

A race is an attempt to accomplish something before someone else does. It doesn't have to be a physical race through space; it can also be a race to construct something, to accumulate something, or to do practically anything else. Normally we think of races as peaceful, involving competition without conflict, but, of course, they can be combined with conflict as well. Because races put time pressure on the player, they discourage careful strategic thought and instead encourage direct, brute-force solutions. If the player has only 15 seconds to get through a host of enemies and disarm a bomb, he's not going to pick them off one by one with sniping shots; he's going to mow them down and charge through the gap, even if it means taking a lot of damage.

Puzzles

Far too many kinds of puzzles exist to list here, but a puzzle is primarily a mental challenge. Often a puzzle is presented as a sort of lock that, when solved, opens another part of the game. The player is presented with a series of objects—often objects that are related in ways that are not directly obvious—and he must manipulate them into a certain configuration to solve the puzzle. To solve the puzzle, it's necessary to understand the relationship among the objects, usually by trial and error and close observation. Players normally get all the time they need to solve puzzles. Because different people have differing amounts of brainpower, requiring that a puzzle be solved within a time limit might make the game impossible for some players.

A few games offer puzzles whose correct solution is not made clear at the outset. The player not only has to understand how the puzzle works, but also has to guess at the solution she is trying to achieve. We consider this a case of bad game design: It forces the player to solve the puzzle by trial and error alone because there's no way to tell when she's on the right track. Infidel was one such game. In the final puzzle at the end of the game, to open a stone sarcophagus, the player had to find 1 of 24 possible combinations of objects. There were no hints about which combination was correct; the player simply had to try them all.

Exploration

Exploration is a key element of many games and is often its own reward. Players enjoy moving into new areas and seeing new things, but exploration cannot be free of challenge or it will just become "sightseeing." Sightseers can exhaust the entertainment of your game in such a short time that they won't perceive the value in the game; it will fail to entertain them for long. To prevent this, we design obstacles that make the players work for their freedom to explore.

The simplest sort of obstacle to exploration is the locked door. We don't literally mean a door with a lock in it, but any device that prevents the player from going on until he has done something to unlock it. You can require the player to do an infinite number of things: find a key elsewhere and bring it to the door; find and manipulate a hidden control (usually unmarked) that opens the door; solve a puzzle that is built into the door; discover a magic word; defeat the doorkeeper in a test of skill, either physical or mental; and so on. The trick is to make the challenge interesting and fresh.

Another common obstacle is the trap. A trap is a device that somehow harms the player's avatar when triggered—possibly killing her or causing damage—and, in any case, discouraging her from coming that way or using that move again. A trap is like a locked door with higher stakes: It poses an actual threat to the player. Traps can take a variety of forms:

  • Some fire off once and then are harmless.
  • Others fire but require a certain recycle time before they can fire again.
  • Still others respond to particular conditions but not to others, like a metal detector at an airport.

A player might simply withstand some traps if they don't do too much damage; other traps can be disarmed or circumvented in some way. If a player has no way of detecting a trap and can find it only by falling into it, it's really just the designer's way of slowing the player down. It's not much fun for the player. For players, the real fun comes in outwitting traps: finding and disabling them without getting caught in them. This gives players a pleasurable feeling of having outfoxed you, the designer, even as you were trying to outfox them.

Yet another example is the maze. A maze is an area where every place looks alike, or mostly alike, and the player has to discover how the places are related to get out, usually by wandering around. Good mazes are implemented as a sort of puzzle, in which the player can deduce the organization of the maze from clues found in the rooms. Poor mazes simply put the player in an area and let her find the way out by trial and error.

Illogical spaces are a variant on the maze theme. In old text adventure games, it was not uncommon that going north from area A took you to area B, but going south from area B did not take you back to area A. The relationships among the spaces were illogical. This challenge requires the player to keep a map, because he can't rely on his common sense to learn his way around. In modern games with 3D engines, illogical spaces are more difficult to implement than they were in text adventures. Illogical spaces are now considered an outdated technique, but they still crop up from time to time. If you're going to use them, do so sparingly, and only in places where there's an explanation for it: "Beware! There is a rip in the fabric of space-time!" or some similar excuse—although preferably more original than this one.

Teleporters are the modern equivalent of illogical spaces. A teleporter is any mechanism that suddenly transports the player from where she is to someplace else. Teleporters are often hidden, which means that players trying to explore an area get caught in them and moved elsewhere without warning. If there are many hidden teleporters in an area, they can make it very difficult to explore. Teleporters can further complicate matters by not always working the same way, teleporting the player to one place the first time they are used, but to somewhere else the second time, and so on. They can also be one-way or two-way, teleporting players somewhere with no way to get back, or allowing them to teleport back again.

Conflict

Conflict is a central element of a great many games because it seems almost inherent in the notion of winning and losing. To win a game, you have to beat the other players. The question is how you beat them. If you beat them by attacking them directly in some way, the game is about conflict. This doesn't necessarily mean combat or violence; checkers is a completely bloodless game, but it's still about conflict.

The challenges associated with conflict depend on the following:

  • The scale of the action (from individuals to whole armies)
  • The speed at which the conflict takes place (from turn-based, allowing all the time you want, to frenetic activity)
  • The complexity of the victory conditions (from simple survival to complex missions with goals and subgoals)

Strategy is the mental act of planning: taking advantage of your situation and resources, anticipating your opponent's moves, knowing and minimizing your weaknesses. A strategic challenge is one in which the player must look carefully at the game and devise a plan of action. In a strategic game, the player's chance of winning depends greatly on the quality of her plan. Chance (luck) and missing information interfere with strategy. Chess is the classic strategy game because it contains no element of chance and offers complete information to both players. Nine Men's Morris and Tic-Tac-Toe are also pure, if simple, strategy games. Backgammon is a game with some strategy, but it also depends a great deal on luck.

Pure strategy games favor the player with a certain type of talent, and they appeal most to the kinds of people who have that talent. Because computer games are usually aimed at a broader audience, relatively few offer pure strategy games. They tend to include elements of chance and missing information as well.

Tactics involve putting a plan into execution, the process of accomplishing the goals that strategy calls for. Tactics are also about responding to unexpected events or conditions, which can include new information or bad luck. Even chess has tactics: The unknown quantity is your opponent, and she might make moves that you did not anticipate. Responding to them requires tactical skill.

It's possible to design a purely tactical game with no strategy. A small-squad combat game in which the soldiers are always moving into unknown territory contains no opportunities for strategy—you can't plan if you don't know where you're going or what you're up against—but many for tactics, such as keeping your soldiers covered, taking advantage of their particular skills, and so on.

The business of supporting troops in the field and bringing fresh troops to the front lines is called logistics. Most war games don't bother with logistical challenges such as transporting food and fuel to where they're needed. These activities are generally considered boring and distracting from the main purpose of the game, which is combat. Real armies have whole teams of people responsible for logistics and could never win without this support; computer games have only the player to handle everything, so it stands to reason that he should be concentrating on more exciting tasks such as attack and defense.

However, modern real-time strategy (RTS) games have introduced one important logistical challenge: weapons production. Unlike board war games, in which the player commonly starts with a fixed number of troops, RTSs now require the player to produce weapons and to research new ones from a limited amount of available raw material. The production facilities themselves must be constructed and then defended. This has changed the entire face of war-gaming, adding a new logistical challenge to what was formerly a purely combat-oriented genre.

In role-playing games, the limited size of the characters' inventories presents another logistical challenge. The player must frequently decide what to carry and what to leave behind. Equipping and balancing a party of heterogeneous characters with all that they need to face a dangerous adventure occupies a significant amount of the player's time. Of course, sometimes this is the fault of a badly designed inventory system, in which an apple takes up the same amount of space as a single coin.

On a smaller scale, personal conflict, as a one-on-one or one-on-many challenge, is a key feature of many action games. The player controls an avatar who battles directly against one or more opponents, often at very high speeds. The challenge of personal combat is immediate, exciting, and visceral.

The fundamental challenge in any game based on conflict is survival. If characters can be removed from the field of play by death or any other means, it is essential to preserve their lives or effective playing time, or you cannot achieve the victory condition. In a few games, survival is itself the victory condition and no other achievements are required, but in most, survival is necessary but not sufficient to win.

Survival is about defending one's self, but many games require that the player defend other things as well, especially things that cannot defend themselves. In chess, this is, of course, the king. This challenge requires that the player know not only the capabilities and vulnerabilities of his units, but also those of the thing he is protecting. He must be prepared to sacrifice valuable units to protect the vital item. Lemmings was an excellent game about sacrificing some units to preserve others.

Another important gaming challenge, first used extensively in Thief: The Dark Project, is stealth—the ability to move undetected. This is an extremely valuable capacity in almost any kind of conflict, especially if the player is the underdog. War games occasionally pose challenges in which the victory condition cannot be achieved through combat but must be achieved through stealth. Thief was designed entirely around this premise. Players had to achieve their missions by stealth as much as possible and had to avoid discovery or combat if they could.

The element of stealth introduces considerable complexity into the design and gameplay of war games. The simplest war games are traditionally games of "perfect information," in which both players know everything about one another. Imagine how difficult chess would be if there were an invisible piece somewhere on the board that could be discovered only by accident.

Economies

An economy is a system in which resources move around, either physically from place to place, or conceptually from owner to owner. This doesn't necessarily mean money; any sort of resource that can be created, moved, stored, earned, exchanged, or destroyed can be involved. Most games contain an economy of some sort. Even a firstperson shooter has a simple economy: Ammunition is obtained by finding it or taking it from dead opponents, and it is consumed by firing your weapons. Health points are consumed by being hit and are restored by medical kits. The designer can make the game easier or harder by adjusting the amounts of ammunition and medical kits available, and a player who is running short must meet the challenge of obtaining more somehow.

Economic challenges are defined in terms of the flow of resources. Some games, such as Theme Park, consist only of economic challenges; others, such as first-person shooters, combine both economic and conflict challenges.

In many games, the challenge is simply to accumulate something: wealth, points, or anything else of intrinsic value. The object of the game might be to accumulate more money, plutonium, or widgets than your opponents. This is the basis of Monopoly, of course, and many other games. The game challenges the player to understand the mechanisms by which wealth is created and to optimize them to his own advantage. In the case of Monopoly, it's helpful to mortgage low-rent properties and use the cash to purchase highrent ones because high-rent properties are the real source of wealth toward the end of the game. Players who understand this are at an advantage over those who don't.

Requiring your players to achieve balance in an economy gives them a more interesting challenge than simply accumulating points, especially if you give them many different kinds of resources to manage. The Settlers is a series of games involving complex interactions among resources: Wheat goes to the mill to become flour, which goes to the bakery to become bread. Bread feeds miners who dig coal and iron ore, which goes to the smelter to become iron bars, which then go to the blacksmith to become weapons, and so on. All of these resources have to be produced and transported to establish a balanced economy. Produce too little of a vital item, and the whole economy grinds to a halt; produce too much, and it piles up, taking up space and wasting time and resources that could be better used elsewhere.

A peculiar sort of economic challenge involves looking after a person or creature, or a small number of them, as in The Sims and Creatures. Unlike a large-scale simulation such as Caesar, in which the player must build and manage an entire town, these smaller-scale simulations focus on individuals. The player must meet the needs of each individual and take into account the unique characteristics that differentiate each one from other individuals. The challenge is to make sure their needs are met and perhaps to improve their growth in various ways. The creatures often behave unpredictably, which adds both to the challenge and to the charm.

Conceptual Challenges

Conceptual challenges are those that require the player to understand something new. To the game designer, conceptual challenges are the richest and most interesting to design because they offer the broadest scope for innovation. They can also be difficult to design and even more difficult to program. Conceptual challenges often occur in construction and management simulations, in which the game is simulating processes that the player must come to understand. In Sim City, for example, there is a direct relationship between an efficient transportation system and economic prosperity. The player who does not deduce this will have difficulty with the game. Sim City challenges the player to comprehend this and many other relationships involved in town planning.

Another sort of conceptual challenge occurs in mystery or detective games, in which the object is not merely to accomplish certain feats, but also to examine the evidence and deduce who committed the crime and how. The game Eagle Eye Mysteries is an excellent example of this: Players follow clues, ignore red herrings, and arrive at a theory of the crime, assembling the relevant evidence to demonstrate proof. Planescape: Torment also offered significant conceptual challenges and had several different endings, depending on how the player interpreted a complex and bizarre series of events.

Gameplay Worksheet
  1. What types of challenges do you want to include in your game? Do you want to challenge the player's physical abilities, his mental abilities, or both?
  2. Game genres are defined in part by the nature of the challenges they offer. Have you selected a genre in advance, and if so, what does that imply for the gameplay? Do you intend to include any cross-genre elements, challenges that are not normally found in your chosen genre?
  3. Does the game include implicit challenges (those that emerge from the design), as well as explicit challenges (those that you specify)?
  4. If the game has a story, how does the story influence the gameplay, and vice versa? Do they operate in tandem, or are they effectively separate pieces?
  5. If the player has an avatar, how does the gameplay influence the avatar's appearance and capabilities?
  6. Is the game's collection of challenges a related group, or is it a compilation of unrelated elements? If the latter, does that have any effect on the player's suspension of disbelief?
  7. Given that not all players enjoy the same kinds of challenges, how does the game's target audience influence the challenges it includes? What challenges will you deliberately exclude?
  8. Will the player be required to face more than one challenge at a time? Which ones?

Putting It Together

As we have discussed in this chapter, there is no single aspect of any game that we can point to and identify as the gameplay. That is because gameplay is not a singular entity. It is a combination of many elements, a synergy that emerges from the inclusion of certain factors. If all of those elements are present in the correct proportion and style, we can be fairly sure that the potential for good gameplay is there; consequently, we can presume (but not be certain) that we have a good game. The gameplay emerges from the interaction among these elements, much in the same way as complex automata emerge from the simple rules of Conway's Game of Life.

There is a particular paradox known as the Sorites Paradox or Heap Paradox. It concerns a pile of sand. An observer is asked whether sand is a pile, and the answer is yes. Then a grain of sand is taken away. The question is repeated, and the answer is still in the affirmative. This process continues, and then at some point, the observer will say that it is no longer a pile. The question then posed is to ask why one grain of sand makes a difference between a pile and a nonpile. Can the observer state a specific number of grains of sand that define a pile? It's back to the familiar "argument of the beard": Why is the observer's definition any better than another observer's definition?

The same applies to gameplay, although on a smaller and coarser-grained scale. In a gedanken experiment, we can look at a game and take away an element (or part thereof) of gameplay. (For example, we could disable Mario's ability to turn left in Mario 64.) We can then pose the question "Does it still have gameplay?" We can continue to remove elements or sub-elements and pose the same question. At some point, the game will be sufficiently crippled for the observer to say that it no longer has gameplay. This point will be different for every observer. Whose opinion is best? That's a question for the philosophers. In short, we cannot define exactly how many gameplay elements are required to make a game. We cannot even state with certainty which are required and which are superfluous. We can only state that, to have gameplay, we need some or all of these elements; to have a pile of sand, we need some or all of these grains.

Much the same way that we can expect to find elements indicating gameplay, we can expect to find opposing elements that indicate the absence of gameplay. By this, we mean that the inclusion of the particular element could be detrimental to the gameplay or, more rarely, that gameplay is not present at all. The game in question might have included all of the elements expected to indicate good gameplay, but it might have also muddied the mix by including extra unwelcome elements that detracted from the positive effects of the good. We have all played games that were almost perfect, apart from one or two annoying flaws: Maybe the difficulty level ramped too quickly, maybe the controls were unwieldy, or maybe the collision detection was slightly suspect. Whatever the cause, it has the overall effect of taking a potentially superb game and knocking it down a peg or two, reducing it to the rank of failed contender. This determines the difference between the excellent and the merely good.

It would seem fairly obvious to the game designer that she is including some suspect elements to the gameplay and, therefore, would make efforts to eliminate them from the design. This has happened. A particular case of note is Blizzard Entertainment's StarCraft. This game was continually tweaked right up until the point of release, to ensure that the gameplay and unit/unit balance was as good as possible. Even so, they didn't quite get it right, and so the expansion pack, Brood War, made further changes to the unit/unit balance—the most notable being an increase in usefulness of the Terran marine and an overhaul of the air-air and air-ground combat units.

The presence or absence of these elements of gameplay can often be inferred only by the existence of their indications or contraindications. We examine these in more detail in the genre-specific chapters.

This has been an excerpt from Andrew Rollings and Ernest Adams on Game Design from New Riders Press, available now.



Contents
  Introduction
  Pure Challenges
  Applied Challenges

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