Nukes are an especially bad idea to try to pull off with a villain who can do magic. I realize that having a guy who can do magic threatening the city with magical stuff against a crew of non-superpowered people makes things pretty anti-climactic, since they'd have to stop him before his plan was ever enacted, so there'd be no imminent threat. Because, I mean, what kind of long-term planning does whipping up a magical...IDK, flood or something take?
So. Nukes and magic. Dumb ideas.