Collect 5000 pieces of salvage.

Force an enemy to drop dynamite that kills two people when exploding.

Kill 35 enemies with the pistol.

Collect 25% of all relics.

Complete one challenge.

Complete one optional tomb.

Impale an enemy and make him fly through the air for 17 meters - it must stick to the surface

Defeat the Moon.

Kill 10 alien Necromorphs.

Kill a Soldier by TK'ing a grenade or rocket back at them.

Fully upgrade your RIG.

Kill the Snowbeast.

Dismember 500 limbs from living enemies.