The Ninja Turtles are alerted by their master Splinter that they have been careless and discovered fighting the Purple Dragons on TV. Denying this, they set out to break into the Purple Dragons' HQ to get to the bottom of these doppelgÃ¤ngers. Upon doing so, the Turtles discover that their "imposters" are from the '87 series. They escape together, but the '03 Turtles find the '88 team childish as they refuse talk until lunch. They enter a pizza place, only to terrify the citizens, who call the cops; the turtles flee, only for the '03 Turtles and Splinter to capture them. '88 Leonardo explains his team was fighting Shredder over Mutagen in the Technodrome; the dimensional teleporter malfunctioned, sending them all to this world. Checking recent tremor reports, the Turtles find the Technodrome; however, '88 Shredder manages to elude them, forcing his foes to build a portal device to reach their universe for "anti-Technodrome gear". In the meantime, Shredder locates an '03 Shredder on an icy asteroid. After Ch'rell is thawed out, he is contained for vivisection, as he's too insane to work with; however, his adopted daughter, Karai, breaks into and frees him; she had been monitoring his exile.While tracking the Technodrome, the Turtles and Splinter are attacked by Hun and the Purple Dragons, who want their mutagen. Although Hun is in possession of a powerful mutant, Splinter destroys it with the Turtle Truck's missiles. Unfortunately, Hun tackles '88 Donetello into the sewers for the mutagen, becoming exposed; he becomes the very thing he hates - a mutant turtle. He wanders until coming upon the technodrome, now under Ch'rell's control, and vows to serve him again. Ch'rell builds a new exoskeleton for himself, and begins the process of rebuilding the cartoonish fortress into something more worthy of the Shredder; he also improves the Foot bots and mutates the Foot clan. Hun, Bebop and Rocksteady are dispatched to destroy the Turtles, breaking into their lair; it begins crumbling, forcing the Turtles to use their dimensional portal stick to escape into the '87 universe. Splinter is captured by Hun to serve as bait in a trap. Ch'rell uses the dimensional portal, learning there are many parallel universes. He decides to launch an all-out assault on the '03 universe to lure the Turtles out of hiding.Back in the '87 universe, the '03 Turtles meet the '88 versions of April O'Neil and Splinter. The '03 Turtles are welcomed as sons and feel a kinship with the '88 Splinter. After both Donatellos apply their expertise, the Turtles are able to return to the '03 universe with the anti-technodrome gear and the '88 Turtles vehicles: the Party Wagon and Turtle Blimp. They find Casey Jones and April attempting to repel the advancing onslaught, and infiltrate the Technodrome, which now looks like the Death Star. Captured by Ch'rell, the Turtles learn they are not the only versions in the multiverse; he plans to kill the "Prime" Turtles, creating a domino effect that erase every other Turtle in the multiverse. All eight are scanned for shared DNA, seemingly vanishing into oblivion as the Technodrome vanishes to the core universe; however, they were teleported them to safety as her father hasn't considered the consequences. Unfortunately, '03 Shredder has already infiltrated the Turtle Prime universe and is now demolishing it; this causes a chain reaction that begins to literally erase everything and everyone in the '03 universe, including April and Casey. Needing to upgrade their portal device, the Turtles break into Purple Dragon HQ; Hun is waiting for them, wanting revenge for his mutation. However, when he sees the world vanishing, Hun surrenders the upgrade tech just before he's erased.The Turtles accomplish their task and just manage to escape being erased, and are teleported to the black-and-white Turtle Prime universe. To their surprise, their originals attack them for no reason, until they mention Shredder. As part of their plan, the other eight will hide while the Prime Turtles lure '03 Shredder out by insulting his pride. Before he comes out, they are challenged by Shredder Prime, who is comically dispatched by the other hiding Turtles. It turns out Karai has teleported them to safety. With the aid of Splinter, Karai, and even the '88 Shredder and Krang, all twelve Turtles then engage Ch'rell in battle. '03 Shredder's exoskeleton grows thanks to molecular amplification technology from Dimension X, but is knocked into the energy the Technodrome is firing and loses some of his suit. Everyone tries knocking him into the beam, but Rocksteady trips and unplugs the power cable. '03 Shredder begins crushing the Prime Turtles, even though Splinter tells him all of reality will vanish. Too insane to care, '03 Shredder continues to crush the Turtles until '88 tosses explosive throwing stars at Ch'rell's leg, causing him to drop the Prime Turtles. Bebop plugs the beam back in, erasing '03 Shredder from existence.With their foe defeated, the Turtles watch as their respective realities restore themselves. Splinter and Karai note that Ch'rell always returns no matter how he is defeated, but the various characters decide they'll be there to stop him whenever he may rise again. The '88 characters take the Technodrome and return to their homeworld, while the '03 characters use the portal stick to return to theirs. The Prime Turtles decide to go get some pizza to eat, as somewhere else, across time and space, Peter Laird and Kevin Eastman put the finishing touches on the first issue of Eastman and Laird's Teenage Mutant Ninja Turtles, expressing the hope that the book will sell.
Output: Question: Who do the 2003 turtles defeat ?, Answer: 88 shredder