Bruce Wayne may have started off small trying to clean up the streets of Gotham City, but over the years, Batman has become a true lynchpin of the DC Universe – and even the Joker knows it. The “Emperor Joker” storyline by Jeph Loeb, J.M. DeMatteis, and more gave the Clown Prince of Crime the ultimate chance to finally defeat the Dark Knight once and for all. But even with godlike power, the Joker couldn’t deny the truth: it’s Batman’s universe, and he just lives in it.
Taking place across Superman #160-161, Adventures of Superman #582-583, Superman: The Man of Steel #104-105, Action Comics #769-770 and Emperor Joker #1, “Emperor Joker” was a storyline that sees the Joker steal Mr. Mxyzptlk’s 5th dimensional powers and use them to wreak havoc across all of existence as reality’s new ruler. Nobody is safe from his madness – not even celestial beings like the Quintessence, the Spectre, and the almighty Darkseid, Lord of Apokolips can escape the effects of Emperor Joker. Superman’s world especially gets turned upside down. The Man of Steel is branded as the murderer of Lex Luthor and sentenced to Arkham Asylum, which he escapes every night. Lois Lane takes Lex’s place as the DC Universe’s resident bald billionaire baddie. What’s more is that Bizarro is considered the world’s greatest hero and Jimmy Olsen was his best pal – Gravedigger Lad.
Meanwhile, after wiping out the rest of the Bat-Family, the Joker tortures Batman to death every single night, only to bring him back the next day with his memories intact to suffer the same fate all over again. Joker’s unrestrained use of Mxy’s power threatens to tear all of reality apart. Not even a fully powered Man of Steel is able to go toe-to-toe with the Jester of Genocide in a purely physical confrontation. The only way to defeat the Joker is to make him lose faith in himself. Fortunately, the Man of Steel knows just how to do it. Just as Joker seemingly gains the upper hand by ripping out Superman’s heart, Clark points out that Joker still needs Batman, despite all his godlike power. Superman says that the Joker would’ve already wiped Batman from existence if he really could. But when Joker tries to prove Superman wrong by erasing the Dark Knight, he finds he just can’t keep Batman out of his head. As Joker struggles to erase the Caped Crusader, Superman even tells him, “It’s his world. You’re just an annoyance in it.”
This causes the Joker’s confidence to falter, robbing him of his power and saving reality from his destruction. After all, if he couldn’t even erase one human, there’s no way he could wipe out all reality. Fans know just how obsessed the Joker is when it comes to Batman, but this takes his co-dependency to a universal level. Even as a god, he truly can’t function without his greatest enemy there to act as a check and balance. The Joker knows that his universe has no meaning without a Batman to throw himself against – otherwise, he’d have killed him from the beginning.
But this exchange highlights the power that Batman’s mere existence has on DC Comics and its growing Omniverse. There are countless versions of the Dark Knight on countless worlds in each multiverse. Much like Superman, Batman is a multiversal staple, and the DC’s cosmic balance recognizes that in-continuity. Not only does the Joker need Batman, but so does the DC Universe at large.
Bruce Wayne is enough of control freak already, so it’s probably for the best that his memories of these events were taken from him. After all, the last thing anyone wants is for Batman’s ego to get any bigger. But even if he’s unaware, both fans and the Joker know: the DC Universe really revolves around Batman.