Theory and Principles of Game Design

A History of the Amiga, from Ars Technica: Part 1: Genesis Part 2: The birth of Amiga Part 3: The first prototype Part 4: Enter Commodore Part 5: Postlaunch blues Part 6: Stopping the bleeding Part 7: Game on!

When the subject of free versus restricted saving comes up , people often end up conflating the issues of players being free to save their progress at any time and games requiring players to replay certain segments upon failure . The assumption is that the proper response to player failure is for the game to reload the latest save state, thus leading to a framing of the issue of loss of player progress in terms of free versus restricted saving. Unrestricted saving mechanisms are essential in modern games in that they allow players to quit the game at any time without losing progress. This does not, however, mean that loss of progress upon failure is an illegitimate mechanic. Countless commercially successful game designs that purposely incorporate just such a mechanic show quite clearly that loss of progress upon failure is a perfectly legitimate mechanic. Ultimately, the answer to the "free save" dilemma is not to design a game such that progress can never be lost, but to d...

Authors and filmmakers who wish to evoke particular emotions in their audience often rely on the audience's ability to empathize with the characters portrayed in the narrative, and especially with the protagonist. The author sets up situations in which characters experience particular emotions in the hope that the audience will themselves have similar feelings, or at least understand why the characters feel the way they do. The author is in control of the characters' emotions, while the audience's emotions derive from sharing in those characters' feelings and experiences. Game designers who wish to evoke particular emotions have it somewhat more difficult. Unlike books and movies, where the author is in full control of the protagonist, it is the audience itself that is largely in control of a game's principal character or characters. Although designers can script particular emotions into a game's protagonist by taking control away from the player or reducing the...

Here are some differences between ground-level 3D and top-down 2D environments, and their implications for ease of navigation: The way the shapes of objects change as the player moves around the game environment. In 2D environments, rigid objects retain their projected shape as they change position and orientation due to player motion, while in 3D environments their apparent shape can change significantly. The way the angles between objects change as the player orbits around a particular point or travels along a path 1 , as measured from the camera's perspective. In 3D environments the apparent angles between objects are significantly affected as the player moves around, but remain fixed in 2D views. For these reasons, a 2D view is generally more stable than a 3D view, as it doesn't change quite as radically as the 3D view when the player moves around the game world. Furthermore, since the view in top-down 2D games doesn't usually rotate as it does in 3D, a typical 2D...

Softimage XSI has recently been acquired by Autodesk, the company that owns competing packages 3ds Max and Maya. Users who've purchased XSI through its former owner will now have to deal with Autodesk for any licensing and support issues. Since XSI requires the software to be activated online before it can be used, existing users will be at Autodesk's mercy when reinstalling XSI onto their computers following catastrophic data loss or when transferring their license onto a new computer. These users, who purchased XSI with Softimage's particular activation policies in mind, will now be subject to Autodesk's activation policies and may even be required -- if Autodesk should so desire -- to agree to Autodesk's more restrictive licensing terms before Autodesk will agree to activate any copies of XSI purchased before the change of ownership. Perhaps things will turn out okay for current XSI users, but there's no guarantee that will be the case. Whenever you use soft...

F ailure by random numbers can occur whenever the random processes that determine failure aren't significantly influenced by the player's choices, giving players little or no meaningful control over the outcome of their actions. For the most part, games should be designed such that players may improve their chances of success according to the choices they make in the game, giving them meaningful control over their future.

Principle: Avoid responding to the player's actions with behavior that is contrary to reasonable player expectations, as it breaks the implied "contract" between the player and the game designer. Players cannot form a useful mental model of the game world when things happen unexpectedly or without an apparent cause. Players should be able to understand the laws at work in your game's environment, and to make appropriate deductions based on their understanding of those laws. If unexpected or incongruent behavior is desired, players should ultimately be able, by virtue of the game's design, to reconcile such behavior with their operative mental model of the game world -- which by its nature is allowed to change as the game progresses.

Principle: S ometimes a player's mistakes aren't really mistakes . If a player has no good reason to believe a particular action might lead to failure, then failure should not be blamed on the player. F ailure by surprise occurs when the player's actions do not appear as if they should lead to failure, because the relationship between action and outcome is either obscure or counterintuitive, or because the element that makes a particular action lead to failure is presented too late for the player to react to it. King's Quest and Dragon's Lair are known for this kind of failure mechanism, where the wrong move can easily result in unexpected death or failure 1 . A game should generally provide enough clues for players to anticipate danger, and should otherwise give players a fair chance to react to any surprises. Footnotes 1. See Ways to Die/Lose in King's Quest and Let's Fail Dragon's Lair v2.0 ( not safe for work ).

Principle : If a game requires a strategy guide or walkthrough to complete, it's broken. If the game may be completed without one but nevertheless provokes a not insignificant number of players to consult one, it's just as broken as before. Rationale: Completing a game should require no external clues. A player's failure to figure out a particular puzzle without outside help is actually the designer's failure to provide sufficient clues within the game. The game world is missing essential information; the game is broken. Exceptions: If a game mechanic explicitly involves the application of external information, this principle does not apply.

Some questions every game designer should ask during the game development process: Are the game's interfaces and user controls consistent throughout the game? If they're not, is there a good reason why they shouldn't be consistent? Do the inconsistencies make logical sense? Do the controls adhere to known conventions for the game's genre? If not, in what ways is the game's control scheme superior to that of its predecessors? Are there objects in the game that behave contrary to reasonable player expectations? Are there objects that look like they should do something they don't do? Are there objects that do things that are not suggested by their form? Does the player feel lost ("where am I" / "what am I supposed to do next") when I don't intend him to feel that way? If I do intend it, do I have a very good reason for it? Does my approach convey the desired emotions, or is it merely frustrating? Does the game provide sufficient cues for t...

The Game : In Your Face The background: In Your Face is a street basketball game for the original Nintendo Game Boy . At the beginning of every game, a coin-flip animation is shown to represent the practice of flipping a coin to determine which side gets control of the ball. The problem: The coin-flip animation is purely cosmetic, for the human player always gets initial control of the ball. The virtual coin's behavior does not agree with the player's expectation that a coin flip should produce random outcomes, thus the game's implicit promise to the player is broken. The solution: Allow the coin flip to determine who gets control of the ball, or else get rid of the coin flip animation.

The game: Civilization IV The background: Numerous times over the course of the game the player is asked to choose from a list technologies that determine the units and improvements available in play. Certain items on each list are emphasized through the addition of the word "recommended" right next to those items. The problem: The placement of the word "recommended" next to particular items introduces a bias toward those items. This is fine for new players, but for slightly more experienced players the game's recommendations can become an obstacle to uninhibited choice. After all, if the player thinks the game has selected the best of all the available choices, why should he pick anything different? This kind of player lacks the experience necessary to make the best choices on his own, and the game's interface hinders the player's acquisition of such experience by interfering with the free exploration of the game's technology tree. The solution: ...

The game: Zelda: The Wind Waker The background: One of the islands in the game, the largest of the Mother and Child Isles , is impossible to reach on foot. A talking fish that's swimming in the area tells the player he may reach the island by taking "a ride on a whirlwind": "They say that inside the ring of rock that makes up the perimeter of that island, there lives an incredibly beautiful fairy! But the thing is, nobody's ever met her. Supposedly, the only way you'll ever meet her is to take a ride on a whilrwind and drop inside that rock perimeter from the sky above. Doesn't sound easy, fry..." The problem: The fish's suggestion is potentially misleading. In certain areas of the game world the player can use his Deku Leaf to glide over cyclones and be lifted high up in the air, extending his gliding range. Recalling these experiences, some players will improperly deduce they're supposed to ride the small cyclone that's found in the i...

The issue : Certain kinds of games require that players keep one or more specific goals in mind as they play. Players who return to a game after a long absence may find it difficult to remember what they're supposed to do next, which may impede their progress. Resolution: Provide some sort of reminder of the player's unfinished tasks. This may assume such different forms as a list of pending and completed goals (Psychonauts), an in-character reminder of pending goals (Dragon Quest VIII), or a video log of significant cutscenes (Ratchet and Clank: Going Commando). If any of the tasks require knowledge of specific details previously revealed in play, the player should likewise be reminded of those details.

The game : Dragon Quest VIII The background : In a battle against a group of monsters, a player who wishes to attack has to first choose the "attack" option from within the game's "fight" menu, and then pick whichever monster is the player's intended target. The problem : Once the player has defeated every monster except for the last one, the game no longer waits for the player to pick a target. The reason that's a problem is that the player, having become accustomed to performing two actions for each attack, is now required to adapt to a different mode of operation where each attack requires only a single action. A player who presses twice on the action button while expecting a single attack will be surprised to find out that he's actually chosen to attack twice (once for each player character). The solution : Have a consistent interface that requires the player to always pick a target for his attacks. Avoiding inconsistencies is more important th...

Defeating an enemy; overcoming an obstacle; surviving in the face of adversity: success and failure are at the very core of the game-player's experience. Games offer players a number of choices, some of which lead to success and some of which lead to failure or non-success. Together with the challenges presented to the player, the fact that the player might fail lends significance to the player's choices and actions. Although failure can be a negative experience, it is also the very thing that makes success meaningful . There are two kinds of failure in games. One kind of failure concerns the player's inability to satisfy a particular success condition that nevertheless remains satisfiable, and another kind of failure takes place whenever the player encounters a particular failure condition . While the first kind of failure is simply a failure to succeed, the latter kind calls for a particular response to the player's actions. The manner in which a game responds to pl...