Complete 25% of Campaign Mode

Completed "It's Raining Death"

Completed "Pilgrimage of Screams"

Completed "Battle for Bladehenge"

Completed "Exploited in the Bowels of Hell"

Complete one Cooperative Multiplayer game

Finish the game in Easy Mode

Finish the game in Hard Mode

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

Defeat 70 enemies with the M4

Defeat 100 enemies with headshots

Defeat three enemies with one explosion