Why it's a bad idea to headbutt someone twice your size!
Some guy starts a fight with a muscle man over pizza and gets headbutted...
A frustrated basketball player headbutts the hoop and paralyzes himself.
Headbutting glass is probably not the smartest thing to let your goat do.
Tough guy gets knocked da F*** out by a smaller kid. Now that's what I call...
You can almost hear his skull crack on this headbutt.
This was the headbutt heard around the world. The world cup to be exact.