Single-Player Games

Games where each game instance only there is only supports one player.

Some games only requires one player. This because the challenge of winning or finishing it can consist of being able to solve a problem, overcome automated opposition, or to succeed better than others (including oneself) has done in previous game instances. By not requiring any other people, these game designs overcome one of the main problems of being able to play a game - finding a sufficient number of willing participants and time and place to engage in gameplay. One cost for this is that the gaming provided is not a social activity in itself (although the game may support features that allow other types of social interaction during or after game instances). One effect of this is that the activity is not a negotiated social agreement, which means that there are no needs to discuss which house rules to use if any but also that any changes from the official or commonly agreed upon way of gaming can be seen as cheating. Another cost is that the game designers and developers of a Single-Player Game need to construct all the challenges to be part of the game without being able to rely on other players to provide the opposition (and possibly balancing by adjusting their comparativeness to the social situation).

Examples

Solitaire and Peg Solitaire are archetypical examples of traditional Single-Player Games. Other examples of games where a player's challenge lies in puzzle-solving are Sudoku, Continuity, and the Incredible Machine game series. The challenge can be increased by adding time constraints (e.g. Bejeweled, or through requiring dexterity (e.g. Mercury Meltdown or Osmos).

Single-Player Games where the opposition is automated are many. Typically this is through having enemies controlled by the computer (.e.g. God of War series, Need for Speed series, Thief series, Plants vs. Zombies, and Zombiepox) but simply handling the environment can be challenge enough (e.g. Icy Tower and Sims series). Of course, the two types can be combined and often are (e.g. Assassin's Creed 2, Minecraft, the Legend of Zelda series, and the Super Mario series).

When Roleplaying Games were adopted to be run on computers many of them took the form of Single-Player Games, e.g. the Elder Scrolls series, and the Fallout series, and thereby initially being similar to adventure games such as Colossal Cave Adventure and the Zork series, even if the player's character could be part of a group of adventurers. Although massively multiplayer online role-playing games have become very popular after their introduction, single-player version have continued to be popular also, e.g. Fable II and Torchlight. Gamebooks such as The Warlock of Firetop Mountain and the Lone Wolf series show how Roleplaying Games can be Single-Player Games through the book medium.

Many FPS games, such as the Doom series and Quake series, have both single-player and multiplayer versions. Even so, the multiplayer versions can typically be played when alone through the use of computer opponents, and even games designed only as multiplayer games, e.g. the Battlefield series and Left 4 Dead series, can be played alone in this fashion. In contrast, the Lego Star Wars series is a Single-Player Game where a second player can join at any point and play for as long as wanted.

The ESP Game is an interesting example because it is presented to players as a two-player game where you do not know whom you are co-operating with. However, one might be playing against the pre-recorded actions of another player, so what seems like a multiplayer game can actually be a Single-Player Game. While this shows that game designs can confuse players about how many people or players there are in a game, it can also be difficult to control how many are interacting with the game. People can switch places during gameplay so they all have had control over what the game considered to be one player did during gameplay, and in cases of some devices, e.g. multitouch devices many people can at once influence the outcome of Single-Player Games such as Flight Control and Harbor Master. Related to this, the use of aimbots in FPS games such as the Doom series and the Quake series show how humans and computer programs can share control over what one player in the game does.

Using the pattern

A basic question regarding the design of Single-Player Games is if they can be won or not, i.e. if they are Unwinnable Games or not. Those that are winnable make use of Winning by Ending Gameplay since Winner determined after Gameplay Ends only makes sense if there are several players that can win.

One of the main issues in Single-Player Games is to consider how to create challenges without human opposition. Puzzle Solving and Construction are typically ways of achieving this, and can be modulated with Time Limits to achieve Challenging Gameplay. Although Single-Player Games cannot have player opposition, i.e. they have to rely on PvE structures rather than PvP structures, the goals and conflicts can be structured in similar fashion as in Multiplayer Games with Conflicts and Combat through the use of Algorithmic Agents. These can designed to be Enemies which may not be able to win the game, but can be thought of opposition with Eliminate goals or as having Opposing Goals to the player's Survive goal. For example, Pac-Man can be analyzed as a game between the Pac-Man and the ghosts and thereby reveal similarities with Tag, including Role Reversals. Likewise, the use of Units can be used in Single-Player Games to simulate some of the aspects of Teams, especially Team Combos. To avoid having players have to perform all the Excise required to handle all the resistance to their own progress, Dedicated Game Facilitators are appropriate, especially if one wishes to achieve Tension (Game Masters are rarely use for this purpose - probably because having one human facilitator for one player is a steep overhead and a computer-based one will be seen as part of the overall facilitation - but see Sleep is Death).

The ways to achieve Challenging Gameplay can be done somewhat differently in Single-Player Games compared to Multiplayer Games. First, by having players complete Levels, game designers can control what sort of challenges the players should meet and be sure that it is the player and nobody else that managed the previous ones (this of course is under the assumption that it is the same agent behind the player all the time). Second, it is easier to provide Limited Planning Ability since the game can control exactly what information the player has access to, and does not need worry about leakage from other players (but see below regarding Strategic Knowledge). Third, players Freedom of Choice can slowly be increased to ensure Smooth Learning Curves without having to take into consideration other players skill levels. Dynamic Difficulty Adjustment can also be used easier since it may be more difficult to notice (players cannot compare their perceived difficulty with each other) and there is no problem of disrupting Player Balance.

When it comes to which Rewards and Penalties to associate with closures in Single-Player Games, these are quite naturally crafted as Individual Rewards and Individual Penalties. However, Rewards and Penalties may work differently in Single-Player Games due to the possibility to have player specific breaks or modulations of gameplay time, such as Cutscenes and Game Time Manipulation. Other game state manipulations outside the gameplay itself, are trivially possible in Single-Player Games, e.g. Save-Load Cycles. This can make it difficult to enforce Penalties without linking Ultra-Powerful Events to a game's Predetermined Story Structure. Making games Turn-Based have similar effects to the other ways of allowing players to control time flow but may not allow them to avoid Penalties except when this can be achieved through a form of Puzzle Solving.

The use of Spectators allows Single-Player Games to become social activities even if those other players do not directly affect the gameplay or the game state. This can however be achieved in games supporting Construction or other forms of Creative Control since these creations can then be share across game instances through Trans-Game Information. Examples of games supporting this includes NetHack, Spore, and Addventures; online versions of these types of games are sometimes referred to as Massively Single-Player Online Games. In these case the game system handles the transfer of information (with or without the players' knowledge and/or consent) but designers may also wish that players pass various forms of Trans-Game Information between themselves and non-players, and thereby support extra-game Social Interaction. At some level all games support this since players' may wish to share their experience of gaming, e.g. retelling what the Predetermined Story Structure told, telling the narrative of their own gameplay experience, commenting graphical or auditory qualities, or simply Diegetically Outstanding Features. However, there are some gameplay related features of games that can encourage this further. For games allowing players to develop Strategic Knowledge, sharing this is a way to strive for Game-Based Social Statuses or simply engage in Bragging based on Gameplay Mastery. When Gameplay Mastery cannot simply be proven by knowledge, games can support the exchange of this type of Trans-Game Information through giving it concrete forms through Easter Eggs, High Score Lists, Replays, and Achievements. The three last of these give rise to Meta Games that blur the line between Single-Player Games and Multiplayer Games, especially so for the more specific use of Replays to create Ghosts since then gamers can directly compare their performance with other performances during gameplay. Of course, through the use of AI Players a Multiplayer Game can be played alone and thereby functionally be a Single-Player Game. The interest of discussing the Predetermined Story Structures in a game can, for the purpose of extra-game Social Interaction, be augmented through the use of Open Destiny since this can create objective differences in the narrative, and thereby discussions about Replayability and Varied Gameplay. Replayability can also be added to most Single-Player Games by simply adding Scores since then players can try to beat their previous Scores.

Although Roleplaying is commonly associated with Social Interaction, many Single-Player Games also make use of this through presenting game goals as diegetic goals held by the player's Character or Avatar. This can however be ignored by players and thereby make them break the Thematic Consistency. A way to counter this is use Committed Goals, but these need to be Optional Goals as well if one doesn't want to restrict players' Freedom of Choice. Another approach is to use Infiltrate goals, since this requires Roleplaying on the diegetic level. It should be noted that on a general level players can break Thematic Consistency if they play around in games rather than try to fulfill goals presented by the design.

By adding Drop-In/Drop-Out functionality for additional players, Single-Player Games can become Multiplayer Games whenever players wish so.

Supporting Sanctioned Cheating in Single-Player Games provides players with a Freedom of Choice in setting up Player Defined Goals and Creative Control in what type of activity they want to have through interacting with the game. Pottering is an example of such an activity, and one which can especially benefit from Sanctioned Cheating in that players can be less restricted by lack of Resources.

Diegetic Aspects

In single-player games, the Thematic Consistency can be easier to maintain since other players cannot break it (although this problem can be reintroduced through Massively Single-Player Online Games).

Interface Aspects

If one wishes to make it possible for several humans to play a Single-Player Game together, Public Interfaces can be an alternative to Drop-In/Drop-Out. This way, co-located can people to share the interface and thereby have a form of common gameplay experience. This solution may be easier to accomplish in games making use of Units rather than Avatars, since these have already need to have interfaces that support several Focus Loci.

Narration Aspects

Predetermined Story Structures are typically easier to construct for Single-Player Games where the player controls only one Avatar or Character since the structure can concentrate upon this Focus Loci. Further, the design does not have to consider the how the interactions between different players can create complications or special cases. This being said, some Single-Player Games interested in creating narratives, e.g. Fahrenheit and the Sims series, let players control several different Characters. In these cases this is used to either provide several different view points (Fahrenheit) to achieve a Melodramatic Structure or to place the construction of the narrative under the players' Creative Control.

Consequences

Given that Single-Player Games by definition cannot provide opposition from other players, they always have PvE in some sense since they need it. Likewise, since nobody else can affect the game state, they also support Private Game Spaces and a Possibility of Anonymity. This also makes them provide Actor Detachment. Even if Single-Player Games cannot by definition have direct Social Interaction between the players of the same game instance, they can support Social Interaction in several other ways as mentioned earlier (e.g. through Public Interfaces, Spectators or Massively Single-Player Online Games). Since players in most cases do not have to consider when to start playing, and in the case of games with Game Pauses or Turns, Single-Player Games also provide a Freedom of Choice when to play and this satisfies one of the requirements for Ubiquitous Gameplay.

When the consequences of game actions in Single-Player Games are difficult to notice to others when they take place, or when the final sequences of actions are under player control through Reversibility or Save-Load Cycles, these games support Experimenting. When Single-Player Games support Game Pauses or are Turn-Based, they provide the possibility for Drop-In/Drop-Out gameplay for the lone player (in contrast to using Drop-In/Drop-Out to allow additional players to join the game).

Restricting the number of players that can access information from a game to one is a good starting point for creating Detective Structures since one avoids the complication of forcing several players to get information together throughout a game.

Relations

Can Instantiate

Actor Detachment, Detective Structures, Possibility of Anonymity, Private Game Spaces, Ubiquitous Gameplay

with Algorithmic Agents

Conflicts, Combat

with Construction, Creative Control, or High Score Lists

Massively Single-Player Online Games

with Drop-In/Drop-Out or Meta Games

Multiplayer Games

with Achievements, Easter Eggs, High Score Lists, or Replays

Bragging, Game-Based Social Statuses

with Freedom of Choice

Smooth Learning Curves

with Game Pauses or Turn-Based Games

Drop-In/Drop-Out, Freedom of Choice

with Game Time Manipulation

Penalties, Rewards

with Reversibility or Save-Load Cycles

Experimenting

with Sanctioned Cheating

Creative Control, Freedom of Choice, Player Defined Goals, Pottering

with Units

Team Combos, Teams

with Achievements, Diegetically Outstanding Features, Drop-In/Drop-Out, Easter Eggs, High Score Lists, Predetermined Story Structures, Public Interfaces, Replays, Spectators, or Strategic Knowledge

Social Interaction

Can Modulate

Diegetic Consistency, Predetermined Story Structures

with Cutscenes

Penalties, Rewards

Can Be Instantiated By

AI Players together with Multiplayer Games

Can Be Modulated By

Algorithmic Agents, Construction, Dedicated Game Facilitators, Dynamic Difficulty Adjustment, Enemies, Individual Rewards, Individual Penalties, Open Destiny, Public Interfaces, Puzzle Solving, PvE, Replays, Roleplaying, Sanctioned Cheating, Scores, Time Limits, Trans-Game Information, Unwinnable Games, Winning by Ending Gameplay

Possible Closure Effects

-

Potentially Conflicting With

Game Masters, PvP, Social Interaction, Winner determined after Gameplay Ends

with Save-Load Cycles

Penalties

History

An updated version of the pattern Single-Player Games that was part of the original collection in the book Patterns in Game Design.

Acknowledgements

Johan Peitz