Purchase a skill.

Kill an enemy with an enemy's arm.

Regenerate with Splatter Siphon.

Perform a Splatterkill.

Protected Chaffin from the soldiers in the street in Operation Swordbreaker

Reach level 25

Kill 500 zombies

Create a combo weapon

Win first game of Campaign Mode.

Join the rankings.

Hijack 50 vehicles - Dukes style.

Complete 'We've Only Just Begun'.