The Buzz: A source close to Bungie's development says the new game will be darker and grittier than previous titles.

Halo 3 screenshot

Speaking to GameSpot, an unnamed source with knowledge of Bungie's development has revealed that this year Bungie will announce a "darker, grittier" Halo title that doesn't feature Master Chief.

The source told GameSpot that the new game is a spin-off that can be described as a "cross between Ghost Recon and Gears of War". It will be "more bloody, violent and grim" and tell the tale of a battle between UNSC forces and the Covenant.

Expect a fully cooperative squad-based campaign in which a squad numbering as many as eight players will be able to play together over Xbox LIVE.

Microsoft hasn't responded to requests for comment, but Bungie has been hinting at a new game over the previous weeks so it's entirely possible the new game will be unveiled during Microsoft's E3 conference this evening.