Cooperative gameplay

Cooperative gameplay (often abbreviated as co-op) is a feature in video games that allows players to work together as teammates, usually against one or more AI opponents. It is distinct from other multiplayer modes, such as competitive multiplayer modes like player versus player or deathmatch. Playing simultaneously allows players to assist one another in many ways: passing weapons or items, healing, providing covering fire in a firefight, and performing cooperative maneuvers such as boosting a teammate up and over obstacles.

In its most simple form, cooperative gameplay modifies the single player mode of a game, allowing additional players, and increasing the difficulty level to compensate for the additional players. More complex examples exist, however, with broader modifications to the story and gameplay. Some co-op games include a new ending when completed in co-op mode. This new ending is unlocked only when players work as a team to complete the game. For instance, Bubble Bobble features an ending that can only be accessed when two players survive co-op mode, as do some console beat 'em up games such as Double Dragon, Streets of Rage, and Die Hard Arcade.

Co-op gaming can operate either locally—with players sharing input devices or using multiple controllers connected to a single console—or over a network, with co-op players joining an existing game running on a game server via a local area networks or wide area networks. Due to the complexity of video game coding, co-op games rarely allow network players and local players to mix. Exceptions do exist, however, such as Mario Kart Wii or Call of Duty Black Ops, which allows two players from the same console to play with others online.

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