I agree with you Necromancer I do believe that they are pretty evenly matched. Though I say that Sephiroth would end up pulling the majority. I mean Kuja has two forms, regular, and Trance, Sephiroth has three, which are regular, Bizarro, and Safer. Though Kuja's Ultima was one bad move, it could totally incapacitate the entire team in Final Fantasy 9 and it destroyed the planet Terra! Still though you can use the spell Ultima on Sephiroth in Final Fantasy 7 and he seems to handle the move okay, so I say he would have enough durability to last quite awhile against Kuja's magic.