Try casting Zombie? Physical attacks are good
I find casting Mirror/reflect works effectivly, do that and he can't cast curaga on himself and keeps healing you instead. then you just keep obliterating with the physical attacks.
The same way you beat any bad person...attack him until he gives up or dies.
Cast reflect on it.It should prevent from healing itself.Also make sure one of your allies in battle have sensor attached to their weapon.It could help tell when the reflect has wore off.