One of the things that was missing from the original "Left 4 Dead" was melee weapons. Sure, guns, Molotov cocktails, and pipe bombs are cool, but do you really think that those things would be as easily at your disposal when the zombie apocalypse comes? Thankfully, the omission is being rectified in "Left 4 Dead 2," and this off-screen video from the floor of this week's San Diego Comicon shows just how fun (and bloody!) these new additions can be: