Suggested by iKnowledge Jean Grey is a very skilled telepath whose experience with the Phoenix also gave her some real combat abilities. While she probably couldn’t do much to Joker’s mind, she won’t even need too. Joker won’t really be able to defend himself from her physical attacks. He is completely helpless against the Phoenix Force and its unrelenting fire strikes. His best hope would be to trick Jean Grey into looking at his mind, but she is too smart for that. Jean Grey wins.