Kill 20 enemies with environmental objects

Upgrade 5 weapons in Campaign Mode

Use the Deadeye to kill 20 snipers

Get 50 headshot kills in Campaign Mode

Kill 3 or more Military Chimera with a single Grenade

Kill 5 Longlegs in mid-jump

Multi-kill -- 2 enemies with 1 Stalker-Pattern bolter shot.

Multi-kill -- 5 enemies with 1 Frag grenade.

Kill 100 enemies.

Find Nathan Gould

Escape the Battery Park evacuation center

Complete In at the Deep End

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