In Halo multiplayer terminology, a betrayal occurred when a player killed their teammate during a team match. The act of deliberately betraying one or more teammates is referred to as teamkilling.
Background
In order for a betrayal to occur, the betraying player must be completely responsible for the death of his or her teammate. Enemy players must play little or no role in the act. For example, if two players on opposing teams are battling each other, and a third player accidentally kills his already-damaged teammate with a grenade, it will not be counted as a betrayal, and the enemy will be credited with the kill.
Most betrayals occur with the use of explosives, as a result of unanticipated splash damage. Almost all betrayals occurring without splash damage are deliberate, though there are exceptions -- for example, a player may betray a teammate if, while taking a Warthog over a Man Cannon on Halo 3's map Valhalla, they land on their partner.
In Halo 2, deliberate teamkillers are a great hassle to deal with, as such an offense was not ban worthy. In Halo 3, a new option called "Betrayal Booting" was introduced; players that commit too many betrayals can be booted by their most recent victim even during matchmade games, with the teamkiller also receiving an EXP penalty. In Custom Games, "Betrayal Booting" can be set manually, to decide how many betrayals must occur before the player is booted. In most Matchmaking games, the betrayal count is set to two.
In Halo: Combat Evolved
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