Use the A.R.E.S. to kill the Brutalisk in the “Piercing the Shroud” mission on Normal difficulty.
Have 9 Terran units training simultaneously in an Unranked or Ranked game.
Complete all the Guide Three achievements.
Kill 50 units with a single Penetrator Round in the “Belly of the Beast” mission on Hard difficulty.
Score the rank of Gold in all the challenge missions.