Cooperative play

Co-op is a multiplayer gametype found in all Halo games. It allows two or more people to play the campaign together. If one character dies, he or she will respawn with the weapons they began the level with. The player who dies has to wait until the player who is still alive is not engaged in combat and is at a safe location to be able to respawn. If both players are killed, both you restart at the last checkpoint. Additionally in Halo 2, if you are playing on Legendary and either of you dies, both of you have to start at the last checkpoint also, unlike Halo: CE and Halo 3's Co-op mode. In Halo: CE and Halo 2, players two through four will become extra Spartans.

In Halo 3, when there are two players, one player will be Master Chief and the other will be the Arbiter. It is somewhat the same with three players, with the addition of N’tho ‘Sraom as another playable character. If a fourth player is available, the Elite Usze ‘Taham will be playable. It should be noted that the players can not choose who they play as and the game will randomly select who plays as who. Co-op can be played on split screen on Halo and Halo 2, but can be played either split screen or over x-box live in Halo 3.