Piece of cake
Storm the common room and kill everyone without taking damage on veteran.
2/27/2013
11:03:31 AM
Ultra Rare 0.8%
Vehicular Slaughter
Destroy all enemies on vehicles during the prison break.
2/21/2013
5:15:04 PM
Rare 18.5%
The Basics
Complete one of the missions you receive in the mission log.
2/16/2013
8:57:15 AM
Common 89.1%
Mazed and Confused
In Buried, survive an entire round within the maze on round 20 or higher.
1/26/2013
2:59:51 AM
Ultra Rare 0.8%
Completionist
Complete all Extinction challenges and escape in Regular or Hardcore difficulty.
1/25/2013
1:11:59 PM
Ultra Rare 1.6%
Death From Below
In Buried, drop the beat on 10 zombies in one game.
12/21/2012
9:41:29 PM
Ultra Rare 3.6%
The Collector
Buy every weapon off the walls in a single Zombies game.
12/5/2012
8:43:38 PM
Ultra Rare 1.6%
Genius Destroyer
Defeat Monsoon without taking any damage on Hard difficulty or above.
11/24/2012
1:02:41 PM
Ultra Rare 1.4%
Trash Picker
Scavenge 40 items in a single game in Regular or Hardcore difficulty.
10/30/2012
1:04:12 AM
Ultra Rare 1.0%
The Ghost Killer
Confront Rorke (Complete "The Ghost Killer" on any difficulty.)
10/29/2012
8:41:21 PM
Rare 27.4%