Ep 21. Attack of the Mega Shredder!

In "Attack of the Mega Shredder!" from season 3, the villainous Shredder returns and he's bigger and badder than ever before thanks to the aid of a nefarious doppelganger. The episode begins with the turtles going about their business in the city, unaware of the danger looming just around the corner. Soon enough, they're attacked by a monstrous version of their old nemesis, now fused with a massive robotic body.

As the turtles struggle to defend themselves against this new threat, they soon discover that Shredder has teamed up with a shadowy figure who appears to be a version of himself from an alternate reality. This new Shredder possesses all of the original's cunning and skill, making him an even deadlier foe than before. Working in tandem with his new companion, Shredder unleashes wave after wave of attacks on the turtles, threatening to overwhelm them at every turn.

Despite their determination and bravery, it seems that the turtles may be facing their toughest challenge yet. With the help of their allies April and Casey, they devise a plan to take down Shredder once and for all. But even their best-laid plans may not be enough to stop the monstrous villain and his diabolical new partner.

As the battle rages on, it becomes clear that the turtles will need to pull out all the stops if they hope to triumph over Shredder. Will they be able to outsmart their foe and emerge victorious? Or will they fall to the might of the Mega Shredder? Only time will tell in this thrilling and action-packed episode of the popular animated series.