Since 1939, the Batman has stalked the streets of Gotham, taking down small time crooks and costumed freaks alike. Any fan of Batman comics knows that there are certain constants throughout the history of the Dark Knight: Bruce Wayne will ultimately always don the cape and cowl, his sidekick Robin will stand by his side, and he'll always come out on top, no matter the odds. Those three things are basically rules at this point. Even when DC has made some kind of shake up to the status quo, readers always know that eventually things will go back to how they once were. There have been some crazy changes to the status quo, though.

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While many haven't lasted past a particular story or have been erased from continuity, some have stuck and added to the Bat mythos in a big way. CBR has assembled a list of the biggest changes to Batman comics, from all the way in the beginning to the Rebirth era. You'll find new Batman, villains turned heroes, the return of missing members of the Bat family, and even a newly introduced mystery involving the Joker. Follow along as we revisit key moments in Batman's history and how they changed the status quo (without you noticing).

15 JAMES GORDON BECOMES BATMAN

James Gordon as All New Batman

This is perhaps the biggest change to the status quo in recent years. After Batman is seemingly killed in a fight with the Joker during Scott Snyder and Greg Capullo's "Endgame" arc, Gotham needs a new Caped Crusader to protect the city. Geri Powers, leader of the Powers family, has the bright idea to put Jim Gordon in a new Batsuit and make him the first GDPD-sanctioned Batman. But Jim doesn't just have a very fashionable cape-less Batsuit, he also has a mech suit and a gun that shoots Batarangs. It's outrageous.

"Superheavy" told the story of Gordon's Batman, from fighting mutated thugs to facing off against a giant kaiju monster on the rooftops of the city. Gordon's Batman was one of the coolest changes to the mythos and it's kind of a shame that it all ended so quickly. But then again, Bruce Wayne will always be THE Batman.

14 DICK GRAYSON BECOMES BATMAN

dick-grayson-damian-wayne-batman-and-robin

After Bruce was seemingly killed by Darkseid at the end of Grant Morrison's Final Crisis, a big battle for the cowl ensued between Batman's allies and enemies. Who had the right to become the next Batman? It was none other than Dick Grayson, the first Robin. While this wasn't the first time Grayson had taken over as Batman -- this also happened in the "Prodigal" crossover story by Chuck Dixon, Alan Grant, and Doug Moench -- it was definitely the Boy Wonder's longest run as the Caped Crusader.

Morrison's Batman and Robin series offered a fresh take on the dynamic duo. Grayson was a more lighthearted, acrobatic Batman, while Damian Wayne, Bruce's son, was by far a darker incarnation of Robin, thus flipping their classic dynamic. Together, they faced off against all manner of villains, including some of the most depraved ever put on the page. Professor Pyg, in particular, comes to mind.

13 BRUCE IS SENT BACK IN TIME

Batman The Return of Bruce Wayne

Even though Grant Morrison didn't kill Bruce off in "Batman R.I.P." -- which really does sound like the appropriate time to do so -- he did eventually "kill" him off in Final Crisis -- at least that's what fans thought at first. Batman faced off against Apokoliptian tyrant Darkseid in a fight that would bring about the end of the Caped Crusader (but not before mortally wounding the evil god (with a gun of all things -- more on that in a sec).

While the DC Universe mourned the "death" of Batman and Gotham fought over who had the right to become his successor, Bruce Wayne was actually stuck in the past, sent back in time by Darkseid's Omega Beam. In Batman: The Return of Bruce Wayne, Bruce has to fight his way through history, from the age of cavemen to the end of time, in order to return to the Gotham City of the present.

12 THOMAS WAYNE BECOMES A VILLAIN

Doctor Hurt in Batman RIP

If you haven't gathered this already, the Grant Morrison era was a pretty mind-bendingly weird time for Batman. All of a sudden, Bruce had a son named Damian, the Club of Heroes were being hunted down one by one, the Joker had been shot in the head, and Bat-Mite was back. Oh, and Thomas Wayne, Bruce's father, wasn't actually dead! Instead, he'd planned the murder of his wife and son and spent the next few decades building a criminal empire called the Black Hand, which he led as the dastardly Doctor Hurt.

Hurt's main motivation was to destroy the Batman by defaming the Wayne family and erasing Bruce's memory. It turned out that Doctor Hurt was actually Bruce's immortal ancestor and not his father. That didn't make this storyline any less creepy, though, especially when Frazier Irving was on pencils.

11 THREE JOKERS

Three Jokers

It's the question that's haunted Batman for years: who is the Joker? It's the greatest mystery of all. Over the years, many writers have written origin stories for the Joker, including "The Man Behind the Red Hood" by Bill Finger, Alan Moore's seminal The Killing Joke, and Scott Snyder and Greg Capullo's "Zero Year," but none of them have truly revealed the Clown's identity.

But in Justice League Vol. 2 #50 by Geoff Johns and Jason Fabok, Batman began to learn the truth about his archnemesis when he asked the Mobius Chair about the villain's true identity. The answer was simple: there are three Jokers, meaning that Batman has faced several versions of the villain. That would at least explain how the Joker is often able to cheat death. Johns has yet to really flesh this storyline out, but it's already delivered quite the bombshell.

10 BATMAN CLONES HIMSELF EVERY 27 YEARS

Bruce Wayne Clones Himself in 27

Here's a huge game changer brought to you by Scott Snyder and Sean Gordon Murphy. In Detective Comics Vol. 2 #27, an over-sized anniversary issue that featured both a modern retelling of the first Batman story and a couple of short stories, Snyder and Murphy made a huge addition to the continuity: Bruce has created a machine that allows him to create clones of himself every 27 years in order to continue the fight as Batman. While this particular tidbit hasn't been established, it would explain all of the different eras of Batman since 1939.

Snyder has continued to toy with this bit of weird science through the years. The machine has most recently been mentioned in the Dark Days prologue to his Dark Nights: Metal crossover event. Perhaps the new book he's going to do with Murphy down the line will be the culmination of this bit of story.

9 ZERO YEAR

Batman in Zero Year

In 2013, Scott Snyder and Greg Capullo began working on "Zero Year," the third arc in their critically-acclaimed run on Batman. In fact, it will probably be the story they're remembered for the most. "Zero Year" is a retelling of Batman's origin story, which was a huge undertaking at the time, considering that it would replace Frank Miller and David Mazzucchelli's "Batman: Year One" from 1987. The final product was a year-long arc that took bits from Miller's story and the very early work of Bob Kane and Bill Finger.

Add to that Snyder's penchant for epic storytelling, Capullo's love for drawing monsters (the revamped Doctor Death is a sight to see), and FCO Plascencia's extraordinary color work. It's a fantastic story that's more than worthy of being the canonical origin story of the Dark Knight.

8 BRUCE TRIED TO COMMIT SUICIDE AT AGE 10

Batman in I am Suicide

We've always known Bruce is a bit suicidal when it comes to his mission to protect Gotham and take down criminals, but we never could have imagined Tom King's addition to the Bat mythos: right before he decided to devote his life to fighting crime, ten-year-old Bruce Wayne tried to commit suicide with his father's razor. This event has some pretty serious implications for the origin of Batman.

The idea is that Bruce symbolically killed himself as a boy in order to make way for Batman, his true self, is perhaps paramount among his retcons. This changes the bit with the bat crashing through the window from the Frank Miller's "Batman: Year One" just a tad bit, doesn't it? Bruce has given up a lot to be Batman. Apparently even his own life...

7 DAMIAN WAYNE: BATMAN

Damian Wayne in Batman 666

Grant Morrison's most long-lasting addition to the Bat mythos is Damian Wayne, Bruce's son with Talia al Ghul. While we saw the young Wayne become Robin in the present day, Morrison hit us with a freakish vision of the future for a very special issue #666, which the writer took quite literally. In this "what if"-like story, Damian is now Batman and has sold his soul to the Devil in exchange for Gotham's protection in an increasingly turbulent world of war and terror.

Damian faces off against the Third Batman, a former cop trained to replace Batman were the original to die, who arrives in Gotham claiming to be the Anti-Christ. The two face off in a hellish battle to the death as Gotham burns around them. This is perhaps the grimmest vision of the future in all of Batman comics.

6 BATMAN INC.

Batman Incorporated

When Bruce Wayne returned to present day Gotham after being zapped to the past by Darkseid in Final Crisis, he decided that it was time to do things a little bit differently. He established Batman Incorporated, a way to use his influence to fight crime all around the world. He recruited several heroes to his cause, including Mr. Unknown, El Gaucho, Nightrunner, Batwing, the Knight, and even a Bat-Cow if you can believe it.

The great thing about Grant Morrison's time on Batman is that, although he made many major changes to the status quo, most of the stuff was inspired by older stories. The Club of Heroes, Bat-Mite, Zur-En-Arrh, Damian Wayne, Doctor Hurt, all of that stuff was inspired by stories from '50s and '60s.

5 CLAYFACE THE HERO

Clayface in Detective Comics

Basil Karlo is one of the oldest members of Batman rogues gallery. He first appeared in 1940 as a washed-up B-movie actor in a costume with a taste for murder. Some time later, Basil finally transformed himself into the shapeshifting monstrosity we know and love today. Over the years, Clayface has -- ahem -- faced off against the Batman many times, but it's only recently that he's actually joined the Caped Crusader in his quest to protect Gotham.

It's actually one of the most endearing heroic turns in recent years. Batman offers Clayface a chance to turn his life around by joining his team of crime fighters, which the former villain gladly accepts. These days, Clayface offers up quite a bit of comedic relief to James Tynion IV's run on Detective Comics. Not to mention that his shapeshifting powers really come in handy for the Caped Crusader.

4 CASSANDRA CAIN NO LONGER BATGIRL

Cassandra Cain in Detective Comics

Cassandra Cain, who was the first Batgirl to headline her own ongoing series, was one of the most beloved members of the Bat family in the early 2000s. Not that you would know that, because the New 52 reboot completely erased Cassandra from continuity and established that only Barbara Gordon had ever been Batgirl. This really stung Bat fans for a few years.

That is, until Cassandra made her triumphant return in the pages of Batman and Robin Eternal by James Tynion IV and Scott Snyder. The weekly limited series reimagined a bit of Cassandra's origin story. She was still a young assassin, but now she worked for the villainous Mother. Eventually, she turned good and joined Batman's team in the latest run of Detective Comics. She goes by the codename "Orphan." Might she become Black Bat again one day?

3 DICK GRAYSON, SECRET AGENT MAN

Dick Grayson Agent of Spyral

After a fruitful career as the first Robin, Nightwing, and briefly as the Caped Crusader himself, it seemed that Dick Grayson had finally bit off more than he could chew. In 2013's "Forever Evil" crossover event, Grayson was outed to the world as Nightwing and seemingly killed some comic book-y contraption known as the Murder Machine. Such was the end of Grayson -- at least that's what Batman wanted everyone to think, so that he could send his former ward on a mission to infiltrate the spy organization known as Spyral.

Tom King, Tim Seeley and Mikel Janin's Grayson together built one of the major shakeups of the final years of the New 52, which saw the former superhero become a sexy secret agent (this is around the time everyone became obsessed with Grayson's butt) engulfed in all manner of spy games. It was good fun while it lasted.

2 DARK KNIGHT DITCHES GUNS

Golden Age Batman Using A Gun in DC Comics

While Batman has a strict no gun rule these days, he didn't always feel this way, especially in the original stories by creators Bob Kane and Bill Finger, who gave the Dark Knight a pistol with which to punish the dastardly criminals of Gotham. In the first few issues of Detective Comics that starred Batman, the Caped Crusader basically aped the Shadow, the pulp hero who was a clear influence on Kane and Finger's greatest creation. The Shadow has guns, which means Batman had them, too.

That's until Batman #4, when it was established that "The Batman never carries or kills with a gun." Tell that to the dudes in Batman #1, who were mowed down by the Bat's machine gun fire! So that's the story of how one of the Dark Knight's key rules was set, perhaps the biggest status quo change of all time.

1 BATMAN USES A GUN

Batman wields a gun in Year Two

Of course, rules are meant to be broken. Just ask the dude who dresses up as a bat and operates outside of the law to beat the crap out of criminals in alley ways. It's true that Batman has been completely opposed to guns for most of his existence, but that didn't stop him from picking one up to fight the Reaper in "Batman: Year Two" by Mike W. Barr, who is legit one of the most far out writers to ever work on the character. (He also wrote Son of the Demon, which is a bonkers Ra's al Ghul story.)

Not only did Batman start using a gun again, it was the gun that killed his parents! Oh, and he teamed up with Joe Chill, the man who used said gun to kill them! It's really no wonder that this story was erased from continuity a few years later.

What other sneaky ways did DC change Batman? Let us know in the comments!