Clear the mountain pass without alerting the enemy (Mission 1)

Reach a total shot distance of 50km

Kill 50 Suicide Zombies

Complete a mission after losing over 500 units of health

Complete Mission 1

Get a 5-for-1 kill with any sniper rifle

Successfully complete Library of Evil

Survive 15 consecutive waves with each of the 4 characters.

Pick up a Panzerfaust

Successfully complete Cathedral of Resurrection

Sever 1,000 limbs

Inception - Unlock the train door using the keys found on the officers

Inception - Get to the destroyer and launch the torpedo without being spotted