Not only that, Sephiroth has materia and that's the only way he can use magic, right? So he has limitations to what he can use.

Doesn't Kuja just know magic? So not only could he heal himself, he could barrier and shell himself to further protect himself from Sephiroth.


You guys have also forgotten he can control creatures from the mist, and I think make them too. He also has an army of Black Mages.

Sephiroth is extremely strong too, but he doesn't have as many advantages as Kuja. I think the only way Sephiroth would win is if he got close enough to Kuja to use his sword, but I think the chances of that are slim considering all the advantages Kuja has at his disposal.