Manhunt

Man Hunt is a multiplayer mode for Assassin's Creed: Brotherhood. Man Hunt places players in two teams of three or four, in which one team hunts the other. Each round lasts five minutes during which the sole goal of the hunted team is to survive the hunter's onslaught after which roles are reversed and hunter becomes the hunted. This mode can cause players to level up quickly due to the high experience points gained with two or three allies. It is available from level 1.

References

http://www.youtube.com/watch?v=4qeGqO2lSuc - GamerSpawn talks to Games Designer Boris Maniora about the multiplayer aspect of Assassin's Creed Brotherhood,at the Paris Games Week 2010. So far, this is the only news of Man Hunt mode.