Blood Bowl, you're probably aware, is football but with Games Workshop races like dwarves and orcs. This is one of the most brilliantly silly ideas in human history, I feel, and it's resulted in two video games since the tabletop original was released back in the 1980s. People seem quite fond of Cyanide's 2009 game, and now they're making another one, using a new engine. It's due for release this Spring, which is rapidly running out, but before then here's a new video showing the Chaos side in action. You'll find it below.
And here's a lovely bit of text from the YouTube video description, which neatly sums up what Chaos teams are all about:
"While human teams are able to adapt to any kind of game—passing, running, or blocking—Chaos teams have a natural predisposition to a certain type of play style when it comes to a Blood Bowl match, favouring one very specific tactic amongst all: crippling, maiming, injuring, trampling, and killing as many opponent players as possible. And, when only few or no survivor is left, finally caring about the ball to score a touchdown."
So it's the Luis Suarez approach to football, basically. You can find more details about Chaos in this recent dev blog.