Defeat 3 Majini with one grenade or proximity bomb.

Make your first kill as a rookie (in Cause and Effect mission)

Kill 100 monsters with thrown melee weapons

Kill 25 monsters with a chainsaw

Complete all the main quests cooperatively with any number of partners

Defeat Harlow

Make pact with Serpo

Survive the horde on the roof

Gain access to a long-range radio station

Kill special enemies: Grenadier, Thug, Wrestler, Infected, Suicider, Screamer, Butcher, Floater.

Reach Henderson

Successfully defend the tunnel entrance