Beginning in December 2015, Batman/Teenage Mutant Ninja Turtles is a six-part crossover between Batman and Teenage Mutant Ninja Turtles (IDW), the result of a collaboration between DC Comics and IDW Publishing.
The story begins during a battle with Krang, who transports the Turtles, Splinter, the Shredder, and the Foot Clan to an Alternate Universe. Finding themselves in Gotham City, the Turtles meet Batman and clash with his Rogues Gallery while trying to find a way back home.
The miniseries is six issues long, and ran from December 2015 to May 2016. The sequel has been announced to launch in December 2017 and end in May 2018, telling a story of Donatello trying to establish a portal between Turtles' and DC Universe but accidentally getting stuck in Gotham... while Bane got to his world. In February 2019, the Grand Finale of the series was announced. It deals with Batman and the Turtles trying to stop Krang from hauling DC Universe-based tech into Dimension X.
Batman/Teenage Mutant Ninja Turtles provides examples of:
- 20% More Awesome: At one point, Michelangelo tries to determine whether or not Batman is 40 percent more or less awesome than the Turtles based on his morality.
- Always a Bigger Fish:
- Batman holds his own against all four turtles at once in their initial fight. Then Splinter steps in, and uses his superior experience to put Batman on the defensive.
- Averted during Batman and Leonardo's sparring match, which Leo wins.
- Ascended Extra: Krang's only contribution to the first entry in the series was to send the Foot Clan and the Turtles to Gotham City. In the third entry, he's become the Big Bad.
- Badass Normal: The Shredder. As per his IDW incarnation, supernatural resurrection aside, he fights primarily with martial arts and ninjitsu. This is more than enough to put him on equal footing with Batman.
- Broad Strokes: The first comic series seems to take its inspiration from the IDW comic book series, but since it ends with Shredder being arrested, which is never alluded to in that line, it's hard to tell just how faithful it is to that canon.
- Brought Down to Normal: What is slowly happening to the Turtles and Splinter; after analyzing a sample of their blood Batman managed to acquire, Lucius Fox discovers that the mutagen that transformed them is incompatible with the laws of physics in the DC Universe, and thus, they're slowly reverting back to ordinary animals. Part of the plot is the Turtles and Splinter trying to return home before that happens.
- Composite Character: The third crossover is full of these thanks to Krang forcibly merging the Ninja Turtle and Batman multiverses. Bruce Wayne was the child who owned (and named) the pre-mutation turtles, the Turtles wear costumes inspired by the various Robinsnote , and Splinter serves his usual role combined with Alfred's. Characters who aren't merged still have a role in the new universe, like Casey Jones being an honest cop who works with Commissioner Gordon.
- Conspicuous Trenchcoat: After storming out of the Batcave, Raphael briefly dons one of these before Batman pulls up in the Batmobile.
- Cool vs. Awesome: The Batman vs. the Teenage Mutant Ninja Turtles. And later, they team up to fight each other's respective Rogues' Galleries.
- Crossover: Between Batman and the IDW incarnation of the Turtles.
- Divide and Conquer: How Batman largely handles the Turtles initially. Using the Batmobile and his gadgets he's able to either keep them from working together, or get them to actively get in each other's way through superior tactics. When Leo is able to fight Batman one on one, he's able to match Batman skill for skill.
- Did You Just Punch Out Cthulhu?: What leads to the third crossover in the series. Remember the Anti-Monitor? The Dimension Lord of the Antimatter Universe, and a Spacetime Eater who nearly wiped out the entire DC multiverse in Crisis on Infinite Earths? Not only did Krang kill him and steal his technology for his scheme, he repurposed the Anti-Monitor's corpse into a new exosuit.
- The Earth-Prime Theory: The third crossover both uses and subverts this. Krang uses the power of the Anti-Monitor to conquer the "prime" versions of the Ninja Turtles universe (the original black-and-white Eastman and Laird comic) and the Batman universe (the mainline DC Comics version) in order to gain power over all the offshoot universes. However, instead of merging them, he merges the IDW Turtles-verse and the universe of the Batman who crossed over with them previously in order to weaken them so they couldn't fight back as effectively, especially since the IDW Turtles had fought and beaten him several times and knew all his tricks.
- Enemy Mine: In the third crossover the Turtles end up enlisting the aid of Oroku Saki (the original Shredder) to help fight the Laughing Man (a composite version of Shredder and Joker), since Krang having ultimate power over all of existence is bad for him too. Unfortunately, the chaos-loving Joker not only refuses to help, but gladly summons Krang's army to New Gotham while asking "You didn't REALLY think I was going to help, did you?"
- Eviler Than Thou: Penguin initially thinks he's an equal business partner with Shredder when the latter shows up in Gotham. It's not long before Shredder demonstrates otherwise, declaring himself the bigger fish in the pond.
- Greater Need Than Mine: The Turtles stay behind in Batman's universe to help him stop Shredder's scheme, despite knowing that they might regress to normal turtles due to the short timetable.
- I Know Your True Name: Splinter follows Batman to the Batcave and discovers the truth about their impending reversion, as well as Batman's Secret Identity. When he and the Turtles later show up in the Batcave, Splinter is able to convince Batman to help by addressing him as Bruce Wayne.
- Irony: In the third crossover, Shredder calls the Laughing Man out for filling his ranks with "garish imbeciles". April smirks and turns to Alfred, remarking "Can't wait until somebody fills him in about Bebop and Rocksteady."
- Jerkass Realization: Frustrated at their lack of progress in stopping Shredder or finding a way home, Raphael gives Batman a "The Reason You Suck" Speech, outright declaring him to be nothing but "a selfish little rich kid" who beats up bad guys for the fun of it whom he refuses to put his faith in. Raph gets hit with this trope when Batman takes him to Crime Alley, where his parents were gunned down in front of him, and explains how that loss motivates him to do what he does.
- Again in the third crossover, where Raph initially doubts his Prime counterpart's claims that someone is screwing with their universes, nearly coming to blows over it. After the Laughing Man manages to capture Prime Raph and send him back to Krang, Raph sadly admits that he was wrong and says they have to do everything they can to fix reality.
- Let's You and Him Fight: The first meeting between the Turtles and Batman results in a fight, mostly due to Raphael. There's also the inevitable showdown between Batman and Shredder.
- Merged Reality: The third series centers on Krang acquiring DC tech and using it to merge the Turtles' universe with the DC Universe to create a reality he could control at will. In the merged universe, Batman was raised alongside the Turtles by Splinter, Casey Jones is a GCPD officer, and both Batman and the Turtles' Rogues Gallery have been melded together (the Foot Clan with The Joker's gang, for example).
- Motive Misidentification: Early on, Raphael believes that Batman is just a "selfish little rich kid" who puts on a costume and fights bad guys purely for the thrills and fun of it, until Batman takes him to Crime Alley, where he watched his parents die, and explains that it's that loss that motivates him to be a hero.
- Powered Armor: Batman breaks out a set called the Intimidator Suit to combat Shredder and his mutated Rogues Gallery at Arkham.
- "The Reason You Suck" Speech: Raphael dishes one out to Batman after losing his patience with him, unable to see what his brothers find so cool about him:Raphael: I see right through your dumb cape and cowl, Batman. You want to know what you are? You're just a thrill-seeker. You're some rich guy who puts on a costume and punches bad guys because it seems like fun. You chose this life. We didn't. We became what we needed to become to survive. We fight Shredder because if we didn't, he'd have us all killed in our sleep. But you don't care about any of that, do you? That's why we failed. If we hadn't listened to you, we could have snuck into that base and gotten home by now. Shut the whole thing down from the other side. We wouldn't be stuck here. We wouldn't have this death sentence over our heads. And for some idiotic reason, they can't see that. They think you're the hero you pretend to be. But I see the truth. You're just a selfish little rich kid doing all of this for kicks, and that's not someone I'm going to put my faith in.
- Shovel Strike: In Batman/TMNT Adventures, the Scarecrow takes Batman down with a shovel to the side of the head after Batman gets a lungful of the Scarecrow's fear gas.
- The Unreveal: It's mentioned that where Gotham is in the TMNT universe there's only an empty patch of land... but the statement is interrupted before the state is specified.
- Villain Team-Up:
- After his first fight with Batman and the Turtles, Shredder ends up joining forces with Ra's al Ghul.
- The sequel has Bane team-up with various Turtles villains like Baxter Stockman or Bebop and Rocksteady.
- You Have GOT to Be Kidding Me!: Commissioner Gordon's Seen It All, but one look at Batman's newest allies push even his limits of credulity.Gordon: [to himself] Just close your eyes and think about retirement. Somewhere warm where the turtles don't talk.
- Your Magic's No Good Here: The mutagen that transformed the Turtles and some of their enemies gradually loses its effectiveness the longer samples remain in the DC universe, creating the risk that the Turtles and Splinter will turn into normal animals if they don't get home.