Destroy 15 Infested structures at nighttime in the “Outbreak” mission on Hard difficulty.
Locate all of Tosh’s Crew in "The Devil’s Playground” mission on Hard difficulty.
Locate all the Moebius survivors in “The Moebius Factor” mission on Normal difficulty.
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.