Kill 10 enemies with headshots

Finish the game in Normal Mode

Defeat 20 enemies with a single punch, after softening them up with gunfire

Defeat 30 enemies with the Desert - 5

Defeat 100 enemies with headshots

Defeat 50 enemies with stealth attacks

Defeat 30 enemies with the Moss - 12

Defeat 20 enemies with gunfire by aiming while hanging

Defeat 20 enemies with headshots

Kill 10 enemies in a row using akimbo weapons in Single Player or Special Ops.

Defeat 20 enemies with hand-to-hand combat

Kill the away team Zombie.

Earn 4 stars in Special Ops.