A new trailer from Call of Duty Modern Warfare 3 shows off the Spec Ops survival mode in the upcoming military third-person shooter sequel. The clip shows lots of shooting, the perks and upgrades to be earned along the way, and some of the enemies you will face, including explosive dogs and guys in cumbersome body armor. As a bonus there's a scene of an opponent at the receiving end of a nifty smartass kill. The clip is embedded below, guarded by our infallible electronic bouncer.