Suggested by iKnowledge Mai may not have the flashiest deck out there, but her cards get the job done. Joker will have a difficult time going up against her winged warriors and Mai has enough cards to easily take the advantage here. Joker won’t be able to get close to her since a monster will always be on hand to back her up so the fact that he would win in a close quarters fight is rendered meaningless. If only he had a deck of cards of his own. Mai wins.
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The Joker’s insanity may be more realistic and relatable than Malik/Marik’s,, but that doesn’t change the fact that besides his Emperor Joker powers, He could still put Mai in a wheelchair, like Barbara Gordon, by means of his harpoon gun or bullet gun. There’s also his Joker Venom to worry about. He could make Mai laugh herself to death if he applied it.
Keep in mind that when the battle starts all of Mai’s monsters are already on the field though so Joker’s definitely not going to get far with his guns