SPARTAN Group Omega

Spartan Group Omega appears in the trailer for Halo Wars. They're wearing what appears to be Mark IV MJOLNIR armor and armed with BR55 Battle Rifles or a similar variant. The identities of the team are unknown, although given the voice of what appears to be their squad leader, Master Chief does not seem to be among them.

The name "Spartan Group Omega" is strange as the Spartan IIs often colour code their squads (eg Red Team, Blue Team).