Many games are designed to be played many times. In order for these to be interesting, the game must offer new challenges to players or give players new experiences that are perceived as entertaining enough to merit continued playing. The degree to which a game provides these incentives determines its level of Replayability.
Example: Chess and Go have so many possible outcomes that players have very little chance of ever playing two games that are exactly the same. This means that every game session will have new challenges in which players can test their skills.
Example: The multiplayer first-person shooters Team Fortress Classic and Return to Castle Wolfenstein and the Battlefield series allow players to choose a character class to play. This gives them special abilities, which means that beyond the normal differences in gameplay due to varieties in players and levels, players also have different possibilities of what to do and have different roles in their teams.
Replayability can be achieved by letting the challenges differ between game instances, by letting challenges be solved in several different ways, or by letting players compare results between games through Trans-Game Information.
Games that provide Cognitive Immersion and have a huge potential game state space seldom offer players exactly the same challenges and thereby provide one form of Replayability. Dedicated Game Facilitators that are aware of players who have played the game before can change the setup of the particular game instances to provide another way to achieve Replayability by altering the challenges. This can for example be achieved through Reconfigurable Game World, although some games allow the players to reconfigure the Game World without the presence of a Dedicated Game Facilitator. Different challenges are also provided in games that give Varied Gameplay by having roles that players have to choose before gameplay proper begins, and by arranging that these roles have Asymmetric Goals or Asymmetric Abilities.
Letting players complete the game or parts of the game in different ways can be done through Selectable Sets of Goals or otherwise through the support of Varied Gameplay within the game. Optional Goals give Freedom of Choice of how to try and solve the overall game. The Replayability of such games increases by letting the players measure how many Optional Goals they have completed, for example, by using a Score or having Easter Eggs that give access to Inaccessible Areas.
Replayability is often acquired by supporting players to measure the level of their successes or failures. Score and High Score Lists can be used for this in Single-Player Games, and allow the players to have a measure of their Game Mastery, either to let players measure their own skill or to allow a Social Status among other players. Tournaments, with the exception of Polyathlons, allow for a similar type of Replayability as a game is typically played several times to create the outcome of the Tournament. Near Miss Indicators can show players how close they were to succeeding, encouraging them to try again and possibility also increasing their chances of succeeding by the information the provide.
Save-Load Cycles and Reversability provide Replayability on a fundamental level within games. These allow players to do Experimenting and to choose the length of play sessions, but they have little effect, or negative effect, on Replayability of the game as a whole.
Games that are challenging or provide experiences based upon the lack of knowledge of players, i. e., Imperfect Information, are difficult to combine with Replayability. This is due to the Trans-Game Information players acquire when they successfully perform Memorizing of what happens in the game, i. e., when they can apply specific facts learned in one game instance in another game instance. This information can affect Replayability in many ways: Surprises in Narrative Structures will no longer be Surprises, Tension will be less effective when players experience the same situations, Puzzle Solving will become trivial if it is not changed between game instances, Unknown Goals will be known in later game instances, and Exploration will be pointless since the environment is already known to the player. An exception to this is presented by Conceal goals in Multiplayer Games, as the challenges in these are to find new hiding places.
Replayability in a game offers players enjoyment of a game beyond a single game session. For games that require player skill, Replayability becomes automatic as players strive to achieve, test, and show Game Mastery. Similarly, when players have Strategic Knowledge in games, the games have a certain level of Replayability, as players can make use of Strategic Knowledge and improve it between game sessions as Trans-Game Information.
Instantiates: Trans-Game Information
Modulates: Inaccessible Areas
Instantiated by: High Score Lists, Reconfigurable Game World, Strategic Knowledge, Asymmetric Abilities, Tournaments, Conceal, Selectable Sets of Goals, Optional Goals, Asymmetric Goals, Easter Eggs, Freedom of Choice, Game Mastery, Varied Gameplay, Save-Load Cycles, Reversability, Score
Modulated by: Strategic Knowledge, Near Miss Indicators, Cognitive Immersion, Dedicated Game Facilitators, Imperfect Information
Potentially conflicting with: Surprises, Trans-Game Information, Unknown Goals, Memorizing, Narrative Structures, Tension, Puzzle Solving, Exploration