In Mob of the Dead, survive an entire round on the bridge on round 15 or higher.

In Mob of the Dead, open a door without spending points.

In Mob of the Dead, obtain Hell's Retriever.

Rescue Woods.

In Die Rise, reach round 10 before turning on the power.

Help Billy get his bike back. (The Lost and Damned)

In Die Rise, revive yourself.

In TranZit, kill one of the denizens of the forest while it is latched onto you.