WARNING: The following contains spoilers for Batman/Teenage Mutant Ninja Turtles III #6, by James Tynion IV, Kevin Eastman and Freddie E. Williams III, on sale now.

Batman and the Teenage Mutant Ninja Turtles are no strangers to team-ups, with heroes becoming virtually inseparable since their first crossover in 2015 from DC and IDW Publishing. Since then, they've reunited in comic books and, just this year, in an animated adaptation and even in the Injustice 2 video game.

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However, conclusion to their comic book trilogy brings them closer than ever, with the villainous Krang merging the Dark Knight and the Heroes in a Half Shell into one being in the final issue of Batman/Teenage Mutant Ninja Turtles III.

This fusion is brought upon by Krang's newfound power, having gained control of the Multiverse by merging with the Anti-Monitor, the DC supervillain who was the primary antagonist in Crisis on Infinite Earths. That permits the warlord from Dimension X to control the histories, and thus, the very existence, of the populations of those myriad universes.

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The result, in the case of the Bat-Turtle, isn't a clean fusion. Instead, the mutated monstrosity is a painful, asymmetrical miasma of the heroes' forms. Although still vaguely humanoid, limbs of different sizes jut out along the body. Heads are equally distributed, most of which are mangled into dreadful visages. The creature merely lets out an agonizing scream, apparently losing the ability to communicate. None of the heads seems to have much awareness of anything, leaving their mental state highly suspect. The hybrid Bat symbol/Turtle shell emblem on the chest is a cute touch, however.

Unfortunately, the cool-yet-horrifying nature of this fusion isn't explored, perhaps because it's held for the climax. Instead, Batman and the Turtles begin to remember their own lives and universes, namely how their two families were before Krang's meddling. That gives them the mental wherewithal to split themselves apart, and return to their normal forms to defeat Krang.

Thankfully, the rest of the series makes up for this by showcasing a more organic juxtaposition of Batman and TMNT lore. The plot, again the results of Krang's disrupting the timeline, has Batman raised by his butler, The Splinter, along with his brothers, the Teenage Mutant Ninja Turtles. Other characters who are fused include The Joker and The Shredder, who become The Laughing Man, leader of the Smiling Clan.

The Turtles are redesigned with elements of Batman'ssidekicks and partners, such as Robin, Nightwing and the Red Hood. There are even appearances from the pre-Crisis Batman and the original Mirage Comics Teenage Mutant Ninja Turtles. That, possibly more than any other intercompany crossover, truly allows fans to see what it would be like if two unrelated franchises existed side by side in the same universe. Sadly, it does seem to be the last time the characters will team up anytime soon. But, given their origin, perhaps we can hope the Turtles will eventually cross over with Marvel's Daredevil.

Batman/Teenage Mutant Ninja Turtles III #6 is available now.

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