Knock down an enemy with Contact Beam Alt-Fire then kill it with Primary Fire before it stands up

Complete the Drill Ride

Snare the Shard with the Ishimura

Sever all three tentacles of a Lurker with one Line Gun Primary Fire shot (single player only)

Destroy the Tripod Nest

Kill 50 Necromorphs while they are in Stasis (single player only)

Find the Peng treasure

Win the fight at the School

Kill the Tormenter

Stomp 10 Containers

Impale an enemy into a Decompression Window to cause it to blow out

Survive the Train Sequence