You are This Guy, holder of The Knife. Your goal is simple: Knife That Guy. That Guy could be any unfortunate marked guy in a crowd of wandering Other Guys. With every That Guy knived, your murderous fervor (and uncontrollable movement speed) increase. You must use your ability run at dangerously fast speeds and your inexplicable talent to dash at an even more dangerously fast speed to take down each target. But this is not a game of senseless slaughter - knifing anyone other than That Guy comes with consequences. Go long enough without knifing That Guy and The Knife will end up marking you...
Here are some screenshots from the current build of Knife That Guy, which I am soon going to be distributing for beta testing. They show some of the added features, like the knife bombs and rage mode powerup.