Kill 50 supply worth of units within 15 seconds in a Melee game.
Win a Free-For-All Multiplayer Custom Game against 7 Elite A.I. opponents.
Win a 1 vs 4 Multiplayer Custom Game with no Allies against 4 Harder A.I. opponents.
Destroy 10 cloaked or burrowed units in a single Melee game.
Complete all the Outmatched achievements.