Complete 25 quests while playing with at least one co-op partner.

Complete act II.

Kill 250 zombies with modified weapons.

Kill 50 human enemies.

Kill 250 zombies using edged melee weapons.

Kill a Suicider with a grenade.

Complete act I.

Drive a total distance of 10 kilometers.

Create weapons to rival the gods of fire or thunder.

Reach level 10.

Kill a zombie with 10 different melee weapons.

Create a customized weapon.

Finished the [Tutorial] mode.