Win 750 Team Unranked or Ranked games as Zerg.
Kill 50 supply worth of units within 15 seconds in a Melee game.
Score the rank of Gold in the “Harbinger of Death” challenge mission.
Kill a Stank before it kills anything on Hard difficulty.
Survive 15 Infested Horde Attacks in the “Night 2 Die" mode of the “Left 2 Die” scenario.