considering how many evil powers he had and the fact that Leo has not powers he has no shot.

^Good point dermer4ever. I think Cole would win seen as he's more battle-hardened too. Even with less powers he would win cz he understands his opponent on psychological level before fighting, that's what made him so good. He'd make a pretty good guess as to Leo's next/every move

Leo can't die...

BOTH

Leo is near-immortal, look at the many times piper has used her powers against him and he comes back alive and kicking. Plus, powers to heal, stealth (glamour) and his endless amount of knowledge concerning magic would make him either a powerful ally or enemy.