Stay in the air. It greatly helps while fighting him as you can more easily dodge the explosion, iron tail, dig (when he initially goes in,) and the attack where he switches side. Also take note of how he flies off the top of the screen. When he flies up and spins around, he's going to plunge down from the top. When he just flies striahgt up, he's going to come from the side. After he loses enough of his health he will fly in from the sides three times in a row or fly out of the ground three times in a row. If you have a reflector, you can reflect the energy shot when he fires it across the ground, but I don't think it works well when he shoots it down onto you. (I'm pretty sure it explodes on contact.)