Complete the “Echoes of the Future” mission with Zeratul killing 50 Zerg units on Normal difficulty.
Complete 25 missions in the Wings of Liberty campaign on Brutal difficulty.
Complete the “Smash and Grab” mission on Normal difficulty without losing a unit to a Protoss Stone Guardian.
Score the rank of Gold in the “Infestation” challenge mission.
Purchase 10 infantry upgrades from the Armory console.