Win a 1 vs 2 Multiplayer Custom Game with no Allies against 2 Elite A.I. opponents.
Complete all the Elite A.I. achievements.
Win a 1 vs 3 Multiplayer Custom Game with no Allies against 3 Harder A.I. opponents.
Score the rank of Gold in all the challenge missions.
Destroy 40 units with a single unit in an Unranked or Ranked game.