YMMV / Emperor Joker

• Ass Pull: How exactly the Joker scammed Mxy out of his "secret imp name" is glossed over, to say nothing of how he (a largely Gotham-bound criminal whose interactions with Superman's wheelhouse are occasional at best) would even know about such a mechanic in the first place. Indeed, the very idea of fifth-dimensional imps having this weakness was something never even implied before (or since) to readers.^note Notably, the Batman: The Brave and the Bold adaptation streamlined this into Bat-Mite looking to give all his powers... to Batman. And being a crappy shot.
• Continuity Lockout: The appearance of the Linda Danvers/Matrix Supergirl is this for casual reader more familiar with Kara Zor-El since the story never explains what her deal is.
• Crosses the Line Twice: The whole storyline is chock full of these moments. One of the best is probably the Joker playing poker with the corpses of all three (at the time) Robins, or him deciding to get Chinese Food, which means him eating all 1.3 billion Chinese people.
• Spiritual Successor: The story recalls the first Batman/Hulk Crossover, when the Shaper of Worlds gave the Joker reality-warping powers. That story ended with Batman Talking the Monster to Death just as Superman did in this story.

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