Win 15 2v2 Versus A.I. games in a row against Harder opponents.
Win 15 2v2 Versus A.I. games in a row against Elite opponents.
Score the rank of Gold in all the challenge missions.
Win a 1 vs 4 Multiplayer Custom Game with no Allies against 4 Harder A.I. opponents.
Complete all the Outmatched achievements.