A tragically violent DCEU fan theory suggests Ben Affleck’s Batman was even more cruel than the Joker off-screen, prior to the events of Zack Snyder’s Batman v Superman: Dawn of Justice. The DCEU is the first live-action DC franchise to establish a universe filled with heroes and villains in their prime. Batman is a special case within the DCEU, as Ben Affleck’s Dark Knight made his on-screen debut long after taking up the cape and cowl.
Ben Affleck’s Batman portrayal is a controversial one. Not only does Affleck’s Batman spend most of Batman v Superman: Dawn of Justice‘s runtime persecuting Superman due to misplaced anger, but he also kills many criminals without a second thought. Although several live-action Batmen have also killed without remorse, Affleck’s Batman is particularly violent in his crime-fighting methods. To top it off, Batman’s implicit history may have been even more questionable than what the DCEU shows.
Ben Affleck’s Batman May Have Killed His Rogue Gallery Prior To Dawn of Justice
The DCEU’s Batman May Have Snapped After Robin’s Death
Batman v Superman: Dawn of Justice presents a seasoned Bruce Wayne with a penchant for lethal force and little regard for his enemies’ lives. Ben Affleck’s Batman goes as far as branding criminals with his symbol. As he prepares to fight Superman, Batman v Superman: Dawn of Justice reveals that Affleck’s Bruce Wayne is still shaken by Robin’s murder at the hands of the Joker, which led Batman down a dark path that made him abandon his traditional no-kill rule. But while the DCEU only confirms that Batman kills low-level criminals, it’s possible that he also killed most members of his rogue gallery before meeting Superman.
Villains like Mister Freeze, Bane, Poison Ivy, Two-Face, the Penguin, and Scarecrow may have been caught with their guard down by a bloodthirsty Dark Knight
After the Joker killed Robin, Batman might have gone on a killing spree that put a definitive end to his feud with several Gotham criminals. Blinded by rage, Batman might have employed lethal force against any criminal that dared cross his path. Villains like Mister Freeze, Bane, Poison Ivy, Two-Face, the Penguin, and Scarecrow may have been caught with their guard down by a bloodthirsty Dark Knight. Realizing his lethal methods could only make matters worse when dealing with supervillains, Batman might have decided to imprison the rest of his villains at Arkham, including Killer Croc, Harley Quinn, and Deadshot.

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Batman’s mercy probably doesn’t last long, if Justice League‘s Knightmare future is taken into account. When Batman confronts the Joker in Zack Snyder’s Justice League, the Joker torments Batman with Robin’s death, and Batman retaliates by reminding him that Harley Quinn “begged” Batman “with her last breath” to kill the Joker slowly. Batman also mentions that Harley died in his arms, like Robin did. Harley Quinn’s death must come between the events of Justice League‘s present day and Batman’s failure to save Lois Lane before the Knightmare future begins.
Batman’s Broken No-Kill Rule Explains Why He Feared Superman
Batman May Have Been Intimidated By Superman’s Invincible Nature
Batman v Superman: Dawn of Justice‘s opening sequence shows how Bruce Wayne witnesses Metropolis’ Black Zero event firsthand. Beyond Superman’s ever-present danger to humanity, Batman may also feel intimidated by the sight of a potential enemy he can’t kill. If Batman truly killed several of his classic villains prior to the events of Batman v Superman: Dawn of Justice, seeing an invulnerable god come down from the skies and establish his own idea of heroism after getting thousands of innocent civilians killed must feel like a personal insult.
If it weren’t for Lois Lane and Superman’s now-infamous “Martha” line, Batman would have murdered Superman with a Kryptonite spear in cold blood
Another detail that supports the theory that Batman grew accustomed to killing powerful DC characters is the fact that he goes for the kill in his battle against Superman. If it weren’t for Lois Lane and Superman’s now-infamous “Martha” line, Batman would have murdered Superman with a Kryptonite spear in cold blood. And if Batman is willing to kill Superman, it wouldn’t be far-fetched to think he would have been willing to kill less virtuous people like Victor Zsasz and Jonathan Crane right after the Joker killed Robin.

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Apart from Deadshot, Killer Croc, Harley Quinn, and the Joker himself, one of the villains who escaped a similar fate to Batman’s victims is Deathstroke, introduced in Justice League‘s Legion of Doom post-credits tease. Another one could be the Riddler, who appeared in Zack Snyder’s original plans for Justice League sequels, where Edward Nygma died after discovering Darkseid’s Anti-Life Equation. Alfred Pennyworth references Oswald Cobblepot in Batman v Superman: Dawn of Justice, though his “exploding wind-up penguins” comment could be read as disregard for the Penguin’s danger level.
The Snyderverse’s Killer Batman Theory Makes 1 Justice League Scene Even Better
Batman Probably Regrets Sparing The One Villain Who Made Him Kill
Batman teams up with the Joker and Deathstroke in the Knightmare future of Zack Snyder’s Justice League. This marks the first and only time Ben Affleck’s Batman and Jared Leto’s Joker appear together on screen, and it wraps up more than two decades’ worth of unseen in-universe conflict. Besides the usual friction between them, Batman may feel even worse working with his archnemesis if Robin’s murder led Batman to kill most of his rogue gallery. Batman’s rage may have led him to kill dangerous villains, yet he stopped before killing the Joker and now has to witness the end of the world alongside him.

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Zack Snyder’s DCEU projects draw inspiration from the Injustice universe, where Superman kills the Joker. The Snyderverse’s dark tone also derives inspiration from iconic DC Comics storylines like The Killing Joke, which implies that Batman snaps and kills the Joker himself. Despite these sources of inspiration, the remarkably dark Snyderverse lets the Joker survive the apocalypse unpunished. Nevertheless, Batman manages to land a blow on the Joker by killing Harley Quinn. Although the Joker won’t admit it, Harley’s death probably affects him.
Batman’s Broken No-Kill Rule Makes Ben Affleck’s Dark Knight A More Tragic Character
Batman Couldn’t Enjoy His Superhero Status Properly
The bulk of Batman’s DCEU story happened after Robin’s death, and after he decided to drop his no-kill rule. Batman is no longer driven by a search for justice, but instead by a search for vengeance. Unfortunately for him, Batman’s broken no-kill rule taints his career as a world-saving superhero, which starts in the second half of his history as the Dark Knight. Soon after forming the Justice League, everything comes crumbling down again when Superman is corrupted by Darkseid and Batman begins to hatch a plan to sacrifice himself in order to save humanity.