Kill 250 zombies with modified weapons.

Loot 5 Exceptional Weapons.

Set 5 enemies on fire and then kill them with explosives.

Kill 50 human enemies.

Kill a Suicider with a grenade.

Kill a Butcher using an axe.

Reach level 25.

Kill 5 Infected in a row with a single blow.

Kill a Ram using tackle skill.

Kill an Infected with a grenade blast.

Kill 150 enemies using Analog Fighting controls.

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