The team at Bungie has just announced that Halo 3 will feature full four-player co-op in campaign mode online over Xbox Live (or System Link). The option of working as a team opens up completely new Halo 3 campaign experiences. Obviously.

But wait, there's more. Rather than running around campaign levels with two Master Chiefs (albeit in differing colored costumes), the co-op Player One will control Master Chief (as always) while Player Two controls the Arbiter -- and Players Three and Player Four will control two all-new characters.

Check out the full story directly from Bungie at www.bungie.net.

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