Drop-In/Drop-Out

Designed support to handle players coming and going during game sessions in multiplayer games.

Players cannot always participate in whole game sessions, having to stop prematurely to do something else. This causes problems for the game design in how it should keep the game balanced and interesting for the remaining gamers, but another type of problem can occur if the gamers that left wants to come back again to the same game session. For this problem the game design needs have mechanisms for re-introducing players without disrupting game balances nor making the effort of the already present players unrewarded in comparison with the returning players.

Examples

The multiplayer arcade game Gauntlet partly supported players leaving and entering the game during a game session. Players whose character had died could start playing again simply by inserting coins and new players could do the same. There was however no graceful way for a player to leave the game when one had a healthy character since that character would keep the others to that area until the abandoned character died (this meant that leaving was worse the more health the character had).

The Lego Star Wars Series (except the GBA version) supports a second player to at any point join the game with a character, and then leave whenever by simply choosing this option in the game. Given that the gameplay never requires both players and that players can replay levels infinitely the gameplay does not degrade when a player drops out.

All massively multiplayer games need to support Drop-In/Drop-Out since it is impossible to synchronize hundreds or thousands of players spread over the world. This is simplification though, since the game structure may imply dedication to participate (e.g. instances in World of Warcraft) or that emergent gameplay may have entered a critical phase and all players in a local part of the game world need each other (Eve Online is an example of a game where this can occur). The latter can also easily occur in other genres where Drop-In/Drop-Out is supported, e.g. team-based first person shooters such as Counter-Strike, Enemy Territory: Quake Wars, and the Team Fortress Series as well as in real-time tactics games such as World in Conflict.

All game sessions in the Left 4 Dead Series begin with four human characters but only one of them needs to controlled by human gamers. Those not played by humans are computer-controlled but can be replaced by gamers joining the games session. Likewise, if a gamer leaves the game (or loses network connection) the computer takes control over the character without disruption to the other gamers' gameplay. People can even "pause" the game to take their own short breaks while the other gamers continue with a temporary computer substitute.

Using the pattern

The basic mechanics of supporting Drop-In/Drop-Out are typically not the main challenge with using the pattern, rather it is to maintain Challenging Gameplay and Perception of Influence. How this can be done typically depends on if the game is based on Cooperation between the players or not. When games revolve around Conflict rather than Cooperation leaving them can be seen as accepting defeat (indeed, many of them use Player Elimination, e.g. Counter-Strike) and does not need to unbalance gameplay for other players (but see diegetic aspects). Entering the game can be more problematic. New or returning players may not need Player Balance in relation to the old players, but at least need Empowerment or the Illusion of Influence. The former can be achieved by temporarily giving them Privileged Abilities or having Balancing Effects but this risks that existing players feel that their Value of Effort is lost. This can be avoided by instead having games built around Tournaments but this centers the entry and exit points to the beginning and end of specific game sessions.

For games built on Cooperation the issue of Player Balance may also be dealt with through Balancing Effects. However, the risk of old players feeling a loss of Value of Effort is lessened since the players typically have Mutual Goals. An alternative is to not actually reduce the number of players, either through Agents (as for e.g. in the Left 4 Dead Series) or through other players taking on extra roles. The latter is easy to do in Self-Facilitated Games (e.g. in roleplaying systems such as Dungeons and Dragons or GURPS) but require additional account handling in computer-mediated games. The reason these solutions cannot be used for non-cooperative games is than the competition usual is against the other human players and not the other characters so replacing the human with another human or an Agent changes the conflict.

Diegetic Aspects

If players are represented in a game through Avatars it is easy to show the entering or exiting of the game session by simply adding or removing the Avatars in the Game World. The removal can be done without causes discrepancies between the theme and the events (i.e. without introducing Non-diegetic Elements) in the game world if the Avatars represent expendable units that are easy to kill, since players may time their leaving to when they died and abandoned Avatars will probably be killed soon anyway. Introducing new Avatars can be trickier but Spawn Points in close proximity to Inaccessible Areas can provide a diegetic explanation.

For other types of games, the use of Agents can let the deigetic presentation continue undisturbed when players leave.

Interface Aspects

The are typically several reasons for other players to wish to know when another player leaves or joins a game session, e.g. if this will change gameplay, Agents act differently from human players, or if they wish to engage in Social Interaction. This can be done through Status Indicators or Non-diegetic Elements.

Consequences

Drop-In/Drop-Out allows players to have Negotiable Play Sessions in that they do not need to adjust their own play sessions to other players sessions. Besides being able to choose how long time they wish to play, Drop-In/Drop-Out gives the game Interruptability since players can use the functionality to define the breaks in the game session rather than define play sessions.

Finally, since not all players need to start at the same time the pattern supports Late Arriving Players.

Relations

Can Instantiate

Interruptability, Late Arriving Players, Negotiable Play Sessions

Can Modulate

Multiplayer Games

Can Be Instantiated By

Agents, Self-Facilitated Games Tournaments

Can Be Modulated By

Balancing Effects, Privileged Abilities

Potentially Conflicting With

Empowerment, Value of Effort, Challenging Gameplay, Perception of Influence

History

New pattern created in this wiki.

References

Online article describing a Microsoft patent for one type of Drop-In/Drop-Out