Warning: Contains SPOILERS for Teenage Mutant Ninja Turtles: Mutant Mayhem!

Summary

  • Teenage Mutant Ninja Turtles: Mutant Mayhem introduces new origins for Splinter, simplifying his backstory and making him a New York City sewer rat who learns ninjutsu through movies and videos.
  • Baxter Stockman, a well-known villain in the TMNT franchise, is revealed to be the creator of the ooze, a key element that mutates the heroes and villains, linking him to the franchise in a new way.
  • The film shows major transformations in character dynamics, with iconic villains like Bebop and Rocksteady becoming allies with the Turtles, while Shredder is portrayed as working for the Utroms, setting up a new role for him in the future of the TMNT universe.

Teenage Mutant Ninja Turtles: Mutant Mayhem is the start of an all-new TMNT series, and here are the 10 biggest lore and character changes that the film makes to the franchise. Although Teenage Mutant Ninja Turtles: Mutant Mayhem is a love letter to the long-running franchise, the film actually makes some major changes to the series' well-established lore. Some of these are obvious and some of these are obscure, but these 10 lore and character changes will have a huge impact on Teenage Mutant Ninja Turtles: Mutant Mayhem going forward.

Teenage Mutant Ninja Turtles: Mutant Mayhem has finally brought the heroes in a half-shell back to the big screen, with it being the first theatrical TMNT movie since Michael Bay's live-action series. The film is far from a standalone project, with a Teenage Mutant Ninja Turtles: Mutant Mayhem sequel and TV series already being announced. So, TMNT: Mutant Mayhem is only the starting point for an expansive new TMNT universe, with the film setting up many elements that will be carried forward into the future. However, this also means that TMNT: Mutant Mayhem's lore changes are more important than ever.

Related: TMNT Mutant Mayhem: 16 Easter Eggs & References

10 Splinter Gets A New Origin Story

Splinter holds up a wooden rod in TMNT Mutant Mayhem.

Splinter, the father and trainer of the Turtles, has typically had two different origin stories throughout TMNT's history. Splinter has either been the mutated pet rat of ninja Hamato Yoshi, or he has been Yoshi himself, turning into a rat after being in the sewers. However, Teenage Mutant Ninja Turtles: Mutant Mayhem chooses not to adapt either of these stories, with Splinter being a random New York City sewer rat that touches the ooze after finding the Turtles. After being rejected by humanity, Splinter learns ninjutsu through watching movies and instructional videos, with this new approach simplifying his origins.

9 Baxter Stockman Created The Ooze

tmnt baxter stockman

The ooze is one of the most important elements in the TMNT franchise, with it being the substance that mutates TMNT's various heroes and villains. Although it varies from series to series, the ooze is typically either created by the Techno Cosmic Research Institute or by Krang, with the ooze's origins mostly remaining mysterious. However, Teenage Mutant Ninja Turtles: Mutant Mayhem reveals that the ooze was actually an unsanctioned experiment made by former TCRI employee Baxter Stockman, linking the ooze to one of the franchise's most well-known villains.

8 Superfly Isn't Baxter Stockman - He's Baxter's Son

Superfly in TMNT Mutant Mayhem

Although Baxter Stockman is a key part of many TMNT arcs, his most famous storyline involves him accidentally mutating into a villainous fly. The Stockman-Fly is one of TMNT's most iconic villains, but Teenage Mutant Ninja Turtles: Mutant Mayhem makes some serious changes to this character's origins. In the film, the mutant (now named Superfly) is actually a creation of Baxter's, with him treating Baxter like his father. Baxter Stockman is killed off early in the film, giving an early end to the beloved TMNT villain.

7 Baxter Stockman Is Behind All Of TMNT's Mutants

Bebop and Rocksteady in brightly colored animation in Teenage Mutant Ninja Turtles Mutant Mayhem

Bebop, Rocksteady, Leatherhead, Mondo Gecko, Genghis Frog, and the other villain mutants are some of the TMNT franchise's most popular villains, with them each having their own origins and storylines. However, TMNT: Mutant Mayhem opted to avoid these origin stories, with each of the film's mutants instead being created by Baxter Stockman. Stockman seemed to create all of these characters from scratch using the ooze, with them being produced in his lab rather than formerly being regular animals or humans.

Related: TMNT Mutant Mayhem Ending & Future Set Up Explained

6 Genghis Frog Isn't Part Of The Punk Frogs

Genghis Frog in TMNT Mutant Mayhem

Genghis Frog is one of the many mutants seen in Teenage Mutant Ninja Turtles: Mutant Mayhem, but his character may be the one that is changed the most drastically. Originally, Genghis Frog was a member of the Punk Frogs, a rival team of teenage mutant ninjas that are created by Shredder and Krang. However, the four frogs get lost in the Florida Everglades, growing up to become allies of the Turtles. TMNT: Mutant Mayhem strangely only features Genghis Frog while not mentioning Attila, Napoleon, and Rasputin, with Genghis Frog also explicitly being a villain.

5 Humans Can't Be Turned Into Mutants

tmnt superfly family

One of the biggest changes in TMNT: Mutant Mayhem is only briefly mentioned, with it being part of Superfly's master plan. Near the end of the film, Superfly explains that he wants to launch the mutagen into Earth's atmosphere. This would cause all of Earth's animals to mutate, but due to humans not being able to mutate, all of humanity would die. This isn't the case in other TMNT media, with several characters like Splinter, Bebop, and Rocksteady often being portrayed as humans that mutate into their animal counterparts.

4 Major TMNT Villains Become Allies With The Turtles

tmnt mutant mayhem ending

By the end of TMNT: Mutant Mayhem, some of the franchise's most notorious villains are actually allies with the Turtles. For example, Bebop and Rocksteady are by far the Turtles' most iconic mutant villains, with them appearing as secondary antagonists in all kind of TMNT storylines. However, the duo as well as characters like Leatherhead and Wingnut are all friends with the Turtles by the end of the movie, meaning that their stories may not be told in the TV series and sequel.

3 The Utroms Are Already On Earth

TMNT Mutant Mayhem Villain Sequel Setup Shredder

The Utroms are a dangerous alien race in the TMNT franchise, with Krang being the most popular member of the brain-like species. Interestingly, Teenage Mutant Ninja Turtles: Mutant Mayhem implies that the Utroms have already established their presence on Earth, with them living alongside the unknowing humans. Although Cynthia Utrom isn't explicitly revealed to be an alien Utrom in the film, it is almost guaranteed that she is a member of the alien species, meaning that they will be a major threat going forward.

Related: TMNT Mutant Mayhem Soundtrack Guide - Every Song In The Movie & When They Play

2 The Turtles Are Attending High School

Teenage Mutant Ninja Turtles Mutant Mayhem

Although the Turtles have appeared in all kinds of stories, one of the most common TMNT themes is that the ninjas are outcasts that must hide from humanity in the sewers. However, TMNT: Mutant Mayhem shockingly ends with the Turtles leaving the sewers and attending high school, with them being loved by all the human students. While having the Turtles attend high school is an interesting idea, it robs future TMNT: Mutant Mayhem stories of using this thematic arc, which is a strange choice.

1 Shredder Is Working For The Utroms

Shredder isn't TMNT's coolest villain.

Teenage Mutant Ninja Turtles: Mutant Mayhem's mid-credits scene gives a first look at Shredder, the arch-nemesis of the Turtles. However, his introduction in the film is interesting, with Shredder being called upon by Cynthia Utrom to assist in their investigation of the Turtles. Shredder is typically the biggest bad in most TMNT stories, which is why him answering to the Utroms and the TCRI is a lore change with some massive implications. Shredder is being set up as the next big bad in the Teenage Mutant Ninja Turtles: Mutant Mayhem universe, so the ramifications of this change will be seen soon.