i never played the game so REALLY?
edit, what i have seen so far, the same as halo 3 and ODST +: Revange: u kill the player that killed u last time Close call: u kill an enemy w/o shields up headcase!: u kill an enemy that sprints opportunist!: u kill an enemy that r reloding with melee or HS Assist!: yeh, an other kill the one that u have been shooting on Oo First strike!: yeh the first kill that round