The Dink Network

OK I'm stuck. Whats the secret to taking out the wizard on Jewel Mtn? I've tried acid rain, Fireballs, various weapons, and all I can seem to do is get a 1 or 2 point hit on him now and then. The Ghosts seem to go down quickly, but hes worse than the Energizer Bunny©, he keeps going, and going, and going. Need some serious advice.

Try and keep him on the other side of the rock and hit him over it.
Or get round behind him and take the batteries out

Thanks SH.. Tried to get behind him, but he spins faster than the EB.. SO I'll try the rock gambit..