When it is apparent that Donatello’s secondary mutation is causing his body to degenerate, the Turtles and Leatherhead agree they must go directly to Agent Bishop’s headquarters to demand a cure. This scenario proves to be fortuitous as Bishop offers to help the Turtles if they retrieve an ancient piece of technology from the Foot.

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Popularity: 8%

The Turtles continue to deal with the seemingly unstoppable mutant outbreak, but they leave Donatello under care of April and Casey when he becomes very ill. However, Donatello’s illness is not just a cold; he is in the final stages of a secondary mutation that will transform him into a savage beast.

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Popularity: 6%

When the power goes out in their lair, the Turtles and Splinter gather around the candlelight as Leonardo tells a story he learned from the Ancient One about Splinter’s sensei, Hamato Yoshi.

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Popularity: 7%

Having traveled to the past, the Turtles and Renet battle with Savanti Romero and his telepathically controlled dinosaurs as Savanti attempts to change the historic timeline by preventing the dinosaur extinction event.

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Popularity: 3%

Savanti Romero plots his revenge against the Turtles and Renet after they had him banished to the Cretaceous period. Using his magic to manipulate time, Romero lures the Turtles and Renet into a trap to obtain the time sceptre.

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Popularity: 2%

The mutant outbreak continues to spread throughout the sewers and subway tunnels while the Turtles try to contain the threat. Back at Area 51, Baxter Stockman prepares a new body for cerebral transfer despite warnings from Agent Bishop. When Stockman’s body begins to show signs of rejection, he becomes delirious, which leads to a rampage against the person he believes to have caused all his problems, April O’Neil.

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Popularity: 3%

April discovers a distress signal from her Uncle Augie, who became trapped in another dimension years ago. She appeals to Donatello for help and they use April’s puzzle cube to travel across the multiverse. They find Augie, along with his new lizard-like friends, the Brotherhood, who claim they wish to help the inhabitants of Earth. Unfortunately, they soon discover the Brotherhood’s true aspirations are not so benevolent.

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Popularity: 6%

Following the invasion engineered by Agent Bishop, genetic material from the replicated aliens combines with inhabitants of the sewers and surrounding waterways, causing a mutant outbreak. Fearing the spread of outbreak, Bishop sends Baxter Stockman to contain the threat. Meanwhile, the Turtles search for items to furnish their new lair, but now must face the threat of attacking mutants.

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Popularity: 6%

Leonardo returns home to find the lair in ruins and his family missing. His search for answers and his family eventually lead him to the realization that Karai is no longer an ally.
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Popularity: 6%

With Leonardo gone, Splinter, Raphael, Donatello and Michelangelo witness the return of the Shredder. They are plunged into the fight of their lives as they ward off volleys of Foot Ninja and Foot Mechs that lay waste to their lair.
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Popularity: 7%