You just have to have a lot of potions and things like that. Then just stay at the side heads, no center unless you want to die quickly. I would be at level 12 or higher. Epuip the strongest keyblade you have. You can hit the fireballs back I think. When it starts to spit black stuff out of it's mouth you can either keep using dodge roll or get on its back. I think it does a shockwave attack if so just jump to dodge it, you can see it coming. Main thing, remember to stay to the side heads.
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