Destroy an enemy Command Center, Hatchery, or Nexus while it is under construction in an Unranked or Ranked game.
Attack for 20 seconds with no counterattacks in an Unranked or Ranked game.
Destroy 10 cloaked or burrowed units in a single Melee game.
Score the rank of Silver in the “Psionic Assault” challenge mission.
Start a conversation with all the main characters.