While its the head: get behind him when he shoots lasers (he always shoots to mid so just get to corner) and spam attacks, you damage him a lot and will level up.
If he turn to skull: just stant in the mid and wait till he flies by to jump and attack him. If he stays in mid run to corner. Made me win vs him very fast with this technique :)
 "WarLight: Multi-Player"){kind=icon}
 "Castle Crashing \"The Beard\""){kind=icon}
 "ELEPHANT RAVE"){kind=icon}