Winter!: Prepare for holiday gaming!
Filling the gaps. Taking place after Halo2 and before Halo 3 ;that means there is no master chief in this game.
You instead play as ODSTs (Orbital Drop Shock Trooper) also refereed to as 'Hell Jumpers', the main ODST in this game is you, the Rookie, but don't worry you'll be able to play as them all.
You find a new alien created by the forerunners that have been captured and used by the covenant, these strange creatures can be your best friend and it is wise not to not get too close to some (covenant left surprise on some that react with human signatures at close distances).
Game Traits applied to Halo 3: ODST (X360) by DesertRecon3