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.
James Tynion IV, Kevin Eastman and Freddie Williams III have turned Batman/Teenage Mutant Ninja Turtles III into quite a crossover, continuing the series' knack for wild stories merging two fan-favorite franchises. This final arc, however, pits them against their most formidable threat ever with an amalgamation of Krang and the Anti-Monitor attempting to remake the Multiverse in their image.
That leads to a huge battle in the final issue, which brings together the heroes from two Prime Earths -- the Gotham reality this series is based on and the Mirage Universe in which the original Turtles exist. But while this crossover delivers plenty of team-ups, it also gives us one we never realized we: Casey Jones and Shredder.
Just to recap, the Mirage Universe was introduced in 1984 by Eastman and Peter Laird, and as Krang/Anti-Monitor says, it's a "progenitor universe" he needs to assimilate. The Mirage Raphael escaped his world early on and entered into the fused Batman/TMNT, where Bruce Wayne became Batman, but was raised by a hybrid Splinter/Alfred, with his Turtle brothers being amalgamations: Leonardo/Nightwing, Raphael/Red Hood, Michelangelo/Damian Wayne and Donatello/Tim Drake. But with the truth unfolding thanks to Mirage Raph, the heroes are split, and they eventually wage war on the Ultra-Technodrome, thus causing both realities to separate as well.
In the conclusion, everyone is coming for Krang/Anti-Monitor. Batman calls in his Bat-family, while the TMNT fight alongside them, with Casey Jones finally being freed from being one of Gotham's cops. April hooks him up with his mask and hockey sticks, and with the Mirage Batman joining the rest of the Mirage Turtles, it's the ultimate team-up against Krang/Anti-Monitor's drones. The icing on the cake, though, is Oroku Saki, aka the Shredder ,being brought in for the fight, working as Casey's partner and giving us banter we never thought we'd get.
It's better than any iteration of Batman and Robin, or even the World's Finest with Batman and Superman. Sure, two Dark Knights are here, speaking about unity and family as they take down evil robots, and Red Hood and Nightwing take shots at each other (Dick even jokes he's the Robin who didn't get killed, so that makes him the better fighter). And, as expected, the TMNT and Mirage Turtles riff off each other with amazing chemistry. But the Shredder/Casey dynamic is even richer, as they're two peas in a pod, aggressive and just as cutthroat as ever, except that Casey doesn't believe in killing.
Both are masked up, wielding dangerous weapons and we can even see mutual respect between them. Casey surprisingly instructs "Shred-Head," who's taking his lead, so they and the Foot Clan can cut a path to Ace Chemicals to guarantee safe passage home when the worlds split for good. We've never seen Shredder listen like this nor Casey in such an authoritative position. It's obvious Shredder knows Casey has potential to be as good as Leo or Raphael, and he listens without questioning.
When the dust settles, once the Turtles return home, Shredder escapes off-panel with the Foot while Casey falls into April's arms, but it's clear they were the one-two knockout punch the book needed. We don't know if we'll get a sequel to this story, but fans are hoping for more of this partnership as Shredder proved he could be a hero, and Casey showed us all he really is leadership material after all.