Who would have thought that a billionaire with parental issues who dresses up as a bat would be the most popular superhero there is? Of course, that's putting Batman darkly, but it can't be helped-- he's the Dark Knight. He's so successful at what he does (keeping Gotham safe), he probably keeps running out of Clown-faced madmen to put in Arkham or muscled baddies to beat up. Gotham can get lonely, but thankfully for the Bat, there's no shortage of other intellectual properties wanting him to crossover.
In fact, despite having no superpowers whatsoever, Batman probably has the most crossover events compared to other superheroes in DC, or other superheroes in general. Some of them make sense, while others are simply too wacky or weird to be done again. So, here are some of the craziest Batman crossovers to prove he's the hero everyone deserves but probably doesn't need right now.
10 WITH WATCHMEN'S RORSCHACH
Well, it's not exactly Batman crossing over to another comic book universe but more like him being visited by someone from another title. Nevertheless, it still counts since that character was none other than Rorschach. He's a more psychotic mashup of Batman and The Question from Alan Moore's Watchmen graphic novel. It puts a more realistic and political lens on superheroes and vigilantes.
Hence, in Doomsday Clock (which is Geoff Johns' comic books series tying up the Watchmen universe to the DC one), Rorschach's meeting with Batman just had to happen. To be more precise, it's Rorschach II since the first one got vaporized, but it's him alright. How'd it fare? Batman sent Rorschach to the crazy house after he ate the pancakes Alfred cooked for Bruce-- the nerve!
9 WITH CAPTAIN AMERICA
Captain America is Marvel's own take on the American Way much like Superman is DC's. As you can imagine, such a figure of hope goes well when paired with a borderline antihero like the Dark Knight. Normally, they would have fought just as Batman and Superman did in their first meeting... or occasionally. However, the Batman Captain America met belonged in the Golden Age comic books-- during World War II.
As such, this Batman, thanks to writer John Byrne was rather tame. That's probably for the best since Captain America wouldn't have stood a chance... but that's a topic for another time. All you need to be thinking about for this crossover is the fact that Batman and Captain America fought Nazis together and the Joker thinking the Red Skull is crazier than him for being a Nazi.
8 WITH TARZAN
Bruce Wayne was a billionaire who lost his parents while he's a child, Lord Greystoke a.k.a. Tarzan was also a billionaire who had a "rough" childhood. When the two met each other in a crossover, they instantly became pals. Although, a Bat costume really would have been preferable over a measly tunic for your crotch. Still, Bruce has met crazier costume-wearers, so he's probably unfazed.
The two don't exactly share the same timeline, so the Batman Tarzan met was someone who lives in the 1930s. That means like Captain America, Tarzan was lucky it wasn't the broody and tortured crime fighter he met. The comic story involved Batman helping Tarzan protect an African cult from a two-faced mercenary called Finnigan Dent... sounds awfully familiar.
7 WITH HARRY HOUDINI
Not modern Batman again, of course, but Gotham by Gaslight Batman. That means Batman in his Victorian-era duds where he sports a trench coat instead of a cape. That's a necessary stylistic choice, however, since he bumped into Harry Houdini in one of his comic book crossovers. As it turns out, Houdini blends in well in Victorian Gotham.
Granted, you can put the legendary escape artist anywhere and in any time period and he'd still fit in. The story involves a series of child murders in Gotham where Bruce Wayne learns quite a lot of skills from Houdini himself as they investigate the insidious murders going on in the damned city.
6 AGAINST THE PREDATOR
Sure, Batman has faced more powerful aliens before (and even won) but none of them were as vigilant as he is. So when he got pitted against a Predator-- THE Predator which gave Ahnold and friends a hard time, you know the Dark Knight is up for a challenge. After all, Gotham is a concrete jungle and the Predator excels in such environments.
The premise not too complex either. Predator's alien pod lands in Gotham, it starts looking for victims, and... Batman to the rescue. Except he actually lost in their first encounter. The Predator simply has more advanced gadgets than he does. Bruce had to up his game by building a mech suit and using it in order to defeat the arrogant alien troublemaker.
5 AGAINST THE XENOMORPHS
Since Batman fought and defeated the humanoid extraterrestrial xenophobe, the Predator, he also just had to go up against one of their sworn crossover enemies: the Xenomorphs. It's a tough fight for sure since Batman has no conventional weapons for killing these oversized cockroaches. Nevertheless, he managed and even took down two of them.
The first time was in the Xenomorph's own turf in a rain forest and the second was in Gotham. Bruce even took two of the Xenomorph's eggs to his own Batcave for studying and probably as a token. He also probably thought that they would have made for nice gifts for Superman's birthday.
4 WITH SCOOBY-DOO AND MYSTERY INC.
Jinkies! These crossovers are starting to get crazier. Batman is starting to look like that Hollywood bachelor every other celebrity wants to sleep with for status. Although if you're above the age of 20, then you probably know about this one already. Batman with Robin in tow appeared alongside the Scooby-doo and the Mystery Inc. gang back in 1972 (thank you Hannah-Barbera).
Somehow it still makes sense. Batman is the World's Greatest Detective and the Mystery Inc. is the world's most dysfunctional ones. They complement each other well in hunting down urban legend impersonators. In fact, they even had another adventure just last year in Scooby-Doo! & Batman: The Brave and the Bold.
3 WITH THE TEENAGE MUTANT NINJA TURTLES
The Ninja Turtles are not the first ninjas Batman has ever faced, but they sure are the coolest. Initially, the two fought each other after both sides believed that either was the enemy they're looking for. However, the Turtles were forced to retreat after Batman proved to be a more experienced combatant and ninja (they probably had way too many pizzas and were out of shape).
Later on, both find out that it was Shredder and his Foot Clan who are up to no good in Gotham City. Actually, it's not just Shredder as they eventually discovered that Ra's al Ghul and the League of Assassins had also allied themselves with the Ninja Turtles' archnemesis. That's one heck of a handful for both teams, but after working with each other, they won against the combined evil ninja warlord villains.
2 WITH THE POWER RANGERS
This time around, it's not just Batman's hogging the crossover spotlight but also the Justice League. The Power Rangers accidentally crossed over to the DC universe after Zedd attacked their command center. This messed up their teleportation and one of them was sent to the DC universe (of all places); Batman even thought one of them was a supervillain.
Eventually, all the other Rangers followed and quickly found out that the DC universe was way out of their league. Lucky for them, the Justice League was available to orient them and help them stay alive. It's two of your favorite childhood characters and action figures, what else could you ask for?
1 ... ELMER FUDD
Okay, this one's just full-blown looney (tunes?), at this point and Batman has really gone off the rails. Remember that age-old rivalry between the balding hunter Elmer Fudd and his archnemesis Bugs Bunny? Elmer usually makes a fool out of himself on those; that's what happened here. A human Bugs Bunny somehow tricked Elmer into hunting down the "Bwuce Wayne."
That meant Rabbit Season was over and has been replaced by Bat Season in a special crossover comic book for these characters. Elmer's no slouch here, though; he's a lot more unhinged in this one and channels a sinister noir tone and behavior. Thankfully, Elmer saw the light and teamed up with Batman here after being double-crossed by the wascally wabbit.