Kill 750 additional Zerg units in the “In Utter Darkness” mission on Normal difficulty.
Score the rank of Gold in the “Harbinger of Death” challenge mission.
Kill 50 supply worth of units within 15 seconds in a Melee game.
Score the rank of Gold in the “Rush Defense” challenge mission.
Attack for 20 seconds with no counterattacks in an Unranked or Ranked game.