Score the rank of Gold in the “Psionic Assault” challenge mission.
Score the rank of Gold in the “Path of Ascension” challenge mission.
Complete all the Final mission achievements.
Kill 50 units with a single Penetrator Round in the “Belly of the Beast” mission on Hard difficulty.
Win a 1 vs 2 Multiplayer Custom Game with no Allies against 2 Elite A.I. opponents.