Kill 20 minions.

First kill with fire.

Release Jennings from his Trap.

First kill with a Bat.

First kill with a Crutch.

Killed a Collared Minion with a collar detonation.

Used Health Syringe for the first time.

Find your first Patient File.

Kill first minion.

Unlock first container.

First encounter with Pighead.

Died once.

Kill 2 rappelling enemies in a row before they land on their feet in Single Player or Special Ops.