[A powerful attack Kuja could use is Flare Star.


Consider Kuja just hovers there, throwing spell after spell. All thses spells take time to perform. Raziel, is extremely quick. He could just scale the wall and launch himself at Kuja. Unless Kuja is exactly in the middle of the room and Raziel can't reach him. That would be bad.

But, agility and melee is still on Raziel's side. Kuja needs time to perform thse attacks, and he very well can't do this is Raziel is running everywhere. It would be like that game where you have the hammer and you try to whack the animal that keeps popping out of the different holes. Except, if you don't hit it quick, it will kill you in this instance.