Developer Treyarch put in the Nazi Zombie mode in Call of Duty: World at War as a fun four player mini-game. The zombie mode was an instant hit and was expanded upon in DLC packs for that game, as well as for Treyarch's Call of Duty: Black Ops.
Today, Treyarch and publisher Activision revealed that the zombie content in the upcoming Call of Duty Black Ops II will be highly expanded, with three different game modes. Joystiq reports that one of them is called Tranzit, which takes place in a big open world that can be played as a single player game or with up to three other players.
Survival mode is more like the zombie modes in previous Treyarch Call of Duty games, as players try to stay alive as long as possible against the undead. The third and final mode is called Grief, which puts eight human players into a zombie world. The players are split in teams of two and while they can't directly attack each other, they can indirectly use the game's environment to give the other team some "grief".
The zombie modes will all have stat tracking, leaderboards, better matchmaking and the ability to add in custom zombie game modes. Call of Duty: Black Ops II is scheduled for a PC release on November 12th.