History Main / DropInDropOutMultiplayer

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!Examples:

* ''Left4Dead'' has four characters at all times, regardless of number of players. Joining the game means controlling one of them, leaving means switching them back to AI control.
* The ''{{Lego Adaptation Game}}s'' do this. They typically have a second character following the first player around, and any player who joins instantly takes control of the second character. Quitting the game means that character becomes AI-controlled again.
* ''Rock Band 3'' introduced the ability for players to drop in/drop out at anytime, even during mid-song.
* Playing as Sonic and Tails in ''SonicTheHedgehog2'' or ''VideoGame/Sonic3AndKnuckles'', a player could grab the second game pad at any point to control Tails, while if there wasn't any input for about 30 seconds, the game will start controlling Tails again.

* ''[[{{Civilization}} Civilization 4]]'' had this, though it was a real pain coming into an AI civ where you didn't know where all your units were,a dn had to immediately fortify them all.

* Playing as Sonic and Tails in ''SonicTheHedgehog2'' or ''[=~Sonic 3 & Knuckles~=]'', a player could grab the second game pad at any point to control Tails, while if there wasn't any input for about 30 seconds, the game will start controlling Tails again.

** Similarly for playing as Helper in the SNES version of ''KirbySuperStar'', except the game wouldn't take control of Helper until the second player's character died and was revived by the first.

* Ubiquitous in competitive online games, if for no other reason than to account for the possibility of some players experiencing connection problems in the early days. Now because, especially with MassivelyMultiplayer games having thousands of players in one level, and even many “normal” 100+ player games like ''{{Battlefield}}'' or ''[[VideoGame/EnemyTerritoryQuakeWars Enemy Territory]]'' , it would be almost impossible to get everyone together for a session in unison (though clan and LAN players try valiantly.)

* ''VideoGame/TeamFortress2'': allows players to come and go.

* Coin-op arcade machines (and many franchises originating from them like ''{{Gauntlet}}'') will traditionally have “PLAYER 2 INSERT COIN” flashing perpetually over the upper right corner of the screen where [=P2=]'s HUD goes, so that just dropping a bit of lucre into the corresponding slot will let any passerby join the game. This is especially useful with titles like the 6-player ''XMenArcade''.

* ''DemonsSouls'' and ''DarkSouls'' apply GameplayAndStoryIntegration to this mechanic. The latter has a more comprehensive implementation, with faction allegiance changing the conditions in which players can join or leave another's world.

* ''[[VideoGame/ItadakiStreet Fortune Street]]'' has the "Out To Lunch" option, where a player can take a break from playing and a computer AI will take over until the player opts back in. Notably, earning points allows you to purchase personality traits and roles to assign to your Mii that also determine the AI's general strategy.

* ''TheWarriors'' allowed a 2nd player to control another Warrior character any time they jumped in and when they drop out, the character goes back to AI control.

* Starting with ''VideoGame/NewSuperMarioBrosWii'', Nintendo's new retro games including ''[=~Kirby's Epic Yarn~=]'' and ''DonkeyKongCountryReturns'' take the approach of allowing players to join or leave only inbetween levels, but at least it's better than having to set the number of players ahead of time and have it be fixed. In addition, the forthcoming ''KirbysReturnToDreamland'' will allow players to drop in and out during levels.

* TeamFortress2: allows players to come and go.

* The ''{{Lego Crossover Game}}s'' do this. They typically have a second character following the first player around, and any player who joins instantly takes control of the second character. Quitting the game means that character becomes AI-controlled again.

* Ubiquitous in competitive online games, if for no other reason than to account for the possibility of some players experiencing connection problems in the early days. Now because, especially with MassivelyMultiplayer games having thousands of players in one level, and even many “normal” 100+ player games like ''{{Battlefield}}'' or ''[[EnemyTerritoryQuakeWars Enemy Territory]]'' , it would be almost impossible to get everyone together for a session in unison (though clan and LAN players try valiantly.)

* Starting with ''VideoGame/NewSuperMarioBrosWii'', Nintendo's new retro games including ''[=~Kirby's Epic Yarn~=]'' and ''DonkeyKongCountryReturns'' take the approach of allowing players to join or leave only inbetween levels, but at least it's better than having to set the number of players ahead of time and have it be fixed.

* ''MarioParty'' games allow you to set human players to computer players and vice versa at any time except during cutscenes and minigames.

* Starting with ''NewSuperMarioBrosWii'', Nintendo's new retro games including ''[=~Kirby's Epic Yarn~=]'' and ''DonkeyKongCountryReturns'' take the approach of allowing players to join or leave only inbetween levels, but at least it's better than having to set the number of players ahead of time and have it be fixed.

Since this means remaining playable with a fluctuating number of players, such games are usually either CoopMultiplayer or heavily reliant on bots.

The solution to that problem is DropInDropOutMultiplayer. The ability to join at any time, and just as crucial, the ability to leave at any time (which helps you avoid that annoying problem where your younger brother suddenly doesn't want to play anymore, leaving with a second character just standing there.) These titles have no real distinction between single and multiple-player games, since those initiated as one type can easily turn into the other and back.

In most video games, multiplayer is a matter of choosing the number of players at the start, and then getting a game going. This can be a problem if someone wants to join later. Ever have that situation where you're playing a game alone that you and your sibling both enjoy, then suddenly s/he walks into the room and wants to play?

The solution to that problem is DropInDropOutMultiplayer. The ability to join at any time, and just as crucial, the ability to leave at any time (which helps you avoid that annoying problem where your younger brother suddenly doesn't want to play anymore, leaving with a second character just standing there).

This solves more than just the sibling problem - it also is what allows many online games, particularly ones with large player limits, to truly work. A game is started, then anyone can come and go as they please. Some large games like the ''{{Battlefield}}'' series have 32 or even 64 player limits, and the GameLobby system, which requires players to get together ahead of time in a group and start the game all at once, would simply never allow for such games to work. Even games such as the recently released ''XMenArcade'' benefit from this system, to easily allow many six-player matches to quickly get going.

* By definition, every single MMO (Massively Multiplayer Online game) ever made. By virtue of being about all players coexisting in the same world at once, they absolutely require this trope or else they could not work.
* Likewise, all [=MUDs=] (Multi-User Dungeons). The genre allows roleplaying gamers to join and leave mid-session.
* ''XMenArcade'' uses this to allow for many multiplayer matches with as many as six players, the upper limit. Anyone can join an online or offline game, and offline players can still join their siblings who are playing online.
* The ''{{Battlefield}}'' series does this, as do most multiplayer [[FirstPersonShooter FPSes]], such as ''CallOfDuty''. Considering ''Battlefield's'' high player count - some games in the series allow as many as 64 players at once - this is entirely necessary.

* The ''{{Lego Crossover Game}}s'' do this. They typically have a second character following the first player around, and any player who joins instantly takes control of the second character. Quitting the game means that character becomes AI-controlled again.
* ''Left4Dead'' has four characters at all times, regardless of number of players. Joining the game means controlling one of them, leaving means switching them back to AI control.
* ''WorldInConflict'' is one of the few online RTS games that has this, made possible by the fact that it has no base building, so new players join at any time during a match without any gameplay disadvantage compared to players who've been there from the start. They ''do'' have the disatvantage of having less time to score points and the game also penalizes you for joining the already winning team if there are vacancies in the losing team (reducing the maximum amount of units you can field at once).

* ''SwordOfTheStars'' even allows players dropping out to leave the AI some basic instructions on how to run their empire and password lock their slot, in case they intend to come back and retake command later.
* Some games take the approach of allowing players to join or leave only inbetween levels, but at least it's better than having to set the number of players ahead of time and have it be fixed. Examples of "between level" drop-in/drop-out include ''NewSuperMarioBrosWii'', ''KirbysEpicYarn'' and ''DonkeyKongCountryReturns''.

* In MindJack if you allow your game to be open other players can "hack" into your single player game, to help or to hinder.

* ''SwordOfTheStars'' even allows players dropping out to leave the AI some basic instructions on how to run their empireand password lock their slot, in case they intend to come back and retake command later.

** Similarly for playing as Helper in the SNES version of ''KirbySuperStar'', except the game wouldn't take control of Helper until the second player's character died and was revived by the first.