@Eikichi: Raistlinratt is right on the money. I was using Atma of the Brother Wolf (Dropped from Orthrus previously), and had MDT-25% + Shellra5 fully merited, and barfira. Fire resist was at 245 throughout the fight. I took a few Firaga IVs for like 60 dmg and Flares for 30 etc. It was pretty funny. It's easier just not to stun, since you can gear swap to a MDT set pretty quickly. I had JUST completed my MDT set that day. Best 1mil I've ever spent!
After you beat him he gives an atma that gives superior fire resist. With that and good set of gear it can be easily manageable. Especially if you have SS from spells or previous cure.