Well, if anyone has ever read JLA: Tower of Babel you will know that Batman has contingency plans for every member of the league in case if one of them ever goes rogue one day. That’s the greatest strength of Batman: he will always find a way to win any fight. But that isn’t to say that it won’t be a close fight. What will probably happen is that the Green Lantern would kick his ass, but somehow Batman keeps getting back up again and again until Green Lantern is too beaten up (physically and mentally) that his will will die down and he would be screwed. Batman is a master of survival,combat,and gadgetry. He would probably make a gravity device that would make the Green Lantern heavy, and making flight impossible. So Batman wins.
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