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Player one, as the Master Chief, begins most level and respawns after dying with Human weaponry such as the battle rifle or assault riflewhile the other players, as Elites, begin most levels and respawn with Covenant weaponry such as Covenant carbines and plasma rifles. In addition, all of the Arbiter's lines of dialogue outside of cutscenes are removed. Certain cutscenes and lines of dialogue are altered to reflect the fact that, unlike in the single player mode, the Arbiter never leaves the Chief's side. In Halo 3when there are two players, player one plays as the Master Chief and player two controls the Arbiter.
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Halo 2 was planned for online co-op mode for up to two players on Xbox Live, but due to time constraints Bungie was not able to perfect online co-op for Halo 2the user interface still contains clues as to how Halo 2 would have had co-operative game mode, and it's even more apparent modders were able to activate this game mode. In Halo: Combat Evolved and Halo 2 co-op, when playing a level involving the Master Chiefboth players will control two identical copies of the Chief when playing a Halo 2 level involving the Arbiterboth players will control identical Arbiters. Generally however, the benefit of added players more than makes up for the increased difficulty. Scaling is also found in Halo 4albeit to a less noticeable degree than was present in Reach. In Halo: Reach this tactic is less feasible, because difficulty "scales" in co-op the more players, the greater the difficulty. In many of the other Halo games, players will often attempt to beat Legendary in co-op instead of single player, because they consider Legendary too difficult to attempt alone. Additionally, in Halo 2if two players are playing on Legendary difficulty and either of them die, then both of them have to start at the last checkpoint similar to the effect that the Iron Skull has on cooperative play. If all players are killed, they will restart at the last saved checkpoint. In the sequels, each level has a designated pair of weapons that respawning characters start with. The player who dies has to wait until the player or one of the players who are still alive are not engaged in combat and are at a safe location before they are able to respawn. If one player dies, they can come back to life, or "respawn". Co-op gameplay consists two or more people playing through the campaign as a team. It allows two or more people to play the together through the campaign or dedicated co-op modes.
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