DC's superhero universe came to be in the time of pulp detectives. Mysteries were baked into the stories, and seeing as how Batman and many of his fellow crimefighters are detectives, this has gone on to this day. Throwing mysteries into superhero stories is a good way to keep readers engaged. Over the years, many mysteries have been revealed to readers that changed the face of the DC Multiverse.

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Readers have discovered the biggest mysteries in DC, but sometimes even the people in-universe trying to find them still haven't figured them out. Mysteries take all shapes and sizes in the DC Multiverse and are as plentiful as hydrogen.

10 Batman Learned About His Mindwipes

Images of heroes whose memories were altered by the JLA in DC Comics

The Justice League has some dark secrets. The one that did the most damage to the team was the Justice League mindwipes. Sometimes, enemies would learn the team's identity. Several team members would mindwipe the villains in the Satellite League days, including Zatanna, Green Arrow, Hawkman, Black Canary, and others.

When Dr. Light attacked Sue Dibny, this league within the League went about their business; then Batman came back. He was mindwiped. He knew something was wrong, but never what, and only found out when Despero used his telepathy to restore the memories of the Secret Society of Supervillains.

9 Alexander Luthor And Superboy-Prime Spent Years Tailoring Events To Their Liking

Alexander Luthor and Superboy Prime in DC Comics

The build-up to Infinite Crisis saw multiple events happening at once. From Despero's revelations destroying the Justice League to a new alliance of villains taking power to interplanetary wars starting to a disaster in the magical world to Checkmate taking advantage of Batman's technology, things went to Hell in a handbasket out of nowhere.

Of course, it was soon revealed that all of these things were related. Alexander Luthor and Superboy-Prime, two of the heroes of the Crisis, decided that the resulting universe was too dark. They worked to destroy the heroes they once saved so they could create a perfect Earth by bringing back the Multiverse, picking and choosing which worlds to put together.

8 The Monitor's Identity And Role In The Universe Was A Mystery

The Monitor from DC Comics

The Monitor is known as the opposite number to the Anti-Monitor, a being whose life was all about trying to keep his destructive brother in check. However, that wasn't always readily apparent. At first, the Monitor would bring villains to his Earth-orbiting satellite, offering them weapons and information for pledges of later loyalty.

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Rumors of the Monitor's existence spread among the heroes, so when he brought a bunch to his satellite for help, they were surprised because they thought he was evil. Of course, the real reason for this is that Marv Wolfman created the Monitor, based on a supervillain called the Librarian he made up as a kid before he and George Pérez even came up with the idea for Crisis.

7 Barry Allen Learned The Truth Behind His Mother's Death

Barry Allen's mother pleads with him to fix history from DC Comics' Flashpoint

Barry Allen's return to life was a big deal for the DC Universe, but the return of Reverse Flash meant that things were about to get crazy. Suddenly, his mother died, and his father was convicted of her death, which changed Barry's entire young life. He devoted himself to finding out the truth, something he wouldn't learn until he went back in time to stop her death.

Flashpoint and all of its consequences came from learning the truth about this. Reverse Flash decided to tamper with the past, starting with his own history before moving on to Barry's. Allen's actions to stop her death did untold damage to the timeline.

6 Wally West's Return Led The Titans To Try To Find Why They Didn't Remember Him For So Long

DC Comics' Wally West in Titans Rebirth

Wally West is DC's best Flash, but the New 52 wiped him from existence for reasons known only to Dan DiDio and Geoff Johns. DC Rebirth #1 brought him back into continuity, revealing that he had been removed from existence but could survive in the Speed Force. No one remembered him until he introduced himself to them.

This mystified his friends in the Titans, so they worked together to figure out what had happened. They soon learned it was because of Abra Kadabra, who trapped Wally in the Speed Force and made everyone forget about him, basically doing Doctor Manhattan's will.

5 The New 52 Was Actually Caused By Doctor Manhattan

Pandora's death in DC Rebirth

Not every DC retcon works, and the New 52 is proof of that. At first, it was believed that it was because Barry Allen tampered with time and a being called Pandora, putting together three different timelines together to fix the damage. It set up that the DCU had only existed for five years, but this explanation had huge problems.

DC Rebirth #1, Batman/Flash: The Button, and Doomsday Clock told the truth. Doctor Manhattan came to the DC Multiverse and began tampering with reality, taking away the Justice Society and other sources of hope and five years of history from the Multiverse. The New 52 was an experiment that failed created by an all-powerful manipulator.

4 The Dark Multiverse's Existence Changed What Everyone Knew About The Multiverse

Tales from the Dark Multiverse explores an evil DC characters

DC's Dark Multiverse was full of suffering. It existed within the shadow of the 52 universes, and each world was a corrupted, broken universe that had no hope because all light and energy resided in the Multiverse above. Its existence was a secret known to the Monitors, Perpetua and the Hands, and Barbatos, the dark bat god. Barbatos decided to make use of the inhabitants of these worlds.

The reveal of the Dark Multiverse changed how everyone looked at the Multiverse. These dark worlds were an integral part of the Multiverse as a whole, with beings like Barbatos, Perpetua, and the Dark Knights using its existence as a weapon against the heroes of the DC Multiverse.

3 Power Girl's True Origins Were Unknown Until Infinite Crisis

DC Comics' Power Girl Hugging Earth-2 Superman

Power Girl was the Earth-2 Supergirl, having adventures with her cousin Kal-L and the heroes of the Justice Society. When the Earths were all made into one at the end of Crisis On Infinite Earths, she was still a part of the world, but her origin was unknown. At various points, she was thought to be a Daxomite or an Atlantean, but her lack of family had a terrible effect on her.

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Infinite Crisis revealed the truth, and it was just the old origin. She was a Kryptonian from Earth-2, folded into the world at that point because she had no doppelgänger, as Kara Zor-El had been removed from continuity until Superboy-Prime punches on the walls of the universe brought her back.

2 Red Hood's Resurrection Was A Secret For A Long Time

Red Hood fighting Batman from DC Comics

Many secrets have hurt Batman over the years. The most recent was the return of Red Hood. The first inklings of his resurrection came during the Hush affair, as his casket was empty. Not long after, Red Hood attacked Gotham and Batman discovered that this was Jason Todd. Infinite Crisis revealed that Superboy-Prime punching the walls of the universe changed events; this was how Todd came back to life.

Talia al Ghul found the exhausted former Robin after he broke out of his casket and nursed him back to health, training him as an assassin. This made him a more formidable fighter and set him on his course to attack Batman, who he blamed for his death and the fact he wasn't resurrected.

1 The Multiverse's Existence Revealed The Fates Of The Golden Age DC Heroes

DC Comics' The Flash 123: The first crossover between Barry Allen and Jay Garrick

Earth-2 influenced every alternate world in comics. The heroes of Golden Age DC, including the Justice Society, Superman, Batman, and Wonder Woman, had their World War II adventures there, something the then-current versions of the Trinity didn't remember. Comics told tales of the Justice Society, and Barry Allen grew up reading them.

It was Barry that discovered Earth-2, but that was only the beginning. Soon, Earth-3, Earth-S, and Earth-X were all discovered, and the Multiverse's existence became general knowledge among the heroes. This opened up a whole new can of worms for the heroes of Earth-1.

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