Score the rank of Gold in all the challenge missions.
Survive 15 Infested Horde Attacks in the “Night 2 Die" mode of the “Left 2 Die” scenario.
Win a 1 vs 2 Multiplayer Custom Game with no Allies against 2 Insane A.I. opponents.
Win a Free-For-All Multiplayer Custom Game against 7 Insane A.I. opponents.
Win a 1 vs 4 Multiplayer Custom Game with no Allies against 4 Hard A.I. opponents.
