Strongest batman villian?

i admit that clayface is one of the most regulary occurring bat villains who is really strong, but you forget solomon grundy. he goes at w/bats more than superman or JLA.

Yeah Grundy is one of the Strongest, but I'd have to say Superman. C'mon how many times has the threat of an evil Superman crossed Bats mind, and how many way's does Bat's plan to defeat him. He has about a thousand.

Also those martian's that Batman fought in the JLA. They were Superman level, but Batman kicked the snot out of them!