The old Metagaming games Melee and Wizard would suit nicely.
I think there was a set of updated fan rules kicking around the net but I cannot find them quickly. Might be worth a search or a look at the BGG page for the games.
You could also try something like Wiz War. The rules used to be online, but I don’t know if they still are, and Hirst Arts had details of using their moulds to cast the boards. Looked good.