Warning: Left 4 Dead 2 is rated M for Mature. Zombies. Guts. Blood. Zombies. Guns. More Blood. More Zombies. You get the picture.

Here is the latest Left 4 Dead 2 – The Sacrifice teaser trailer from Valve. This is for the upcoming add-on content that will be available for both Left 4 Dead and Left 4 Dead 2. The Sacrifice is set to be released October 5th.