•
Foot Clan are a ninja clan seeking to resurrect the Shredder and take over New York City. They can make origami ninjas out of paper and have the power of teleportation through hidden gateways. In "How to Make Enemies and Bend People to Your Will", Baron Draxum took command over the Foot after exploiting a loophole in the clan's rulings of leadership. In the episodes "End Game" and "Many Unhappy Returns", it is revealed that the Foot were manipulating Draxum into donning the Kuroi Yōroi so it could drain his life force to reassemble and resurrect Shredder. •
Oroku Saki / Shredder (voiced by
Hoon Lee) is the original leader of the Foot Clan. 500 years ago, Saki was possessed by the demonic Kuroi Yōroi armor, which consumed his soul, after making a deal with a powerful
Oni (Krang) to forge the armor. Shredder terrorized Japan until he was defeated by the Hamato Clan, with his armor being broken into pieces and scattered across the world to prevent his return. The Foot and Baron Draxum began seeking out the fragments of the Kuroi Yōroi to reassemble it and resurrect the Shredder, the latter being tricked into wearing the armor so his life force can be siphoned. Shredder reconstitutes himself after the Turtles break the armor off of Draxum, but becomes a feral beast due to something that went wrong with his resurrection. After regaining his intelligence, Shredder attempts to drain Splinter's essence. With help from the Hamato Clan, the Turtles vanquish the Kuroi Yōroi, destroying the Shredder persona. Oroku Saki survives and is returned to the Hamato clan. • Foot Lieutenant (voiced by
Rob Paulsen) is a leading officer of the Foot Clan. • Foot Brute (voiced by
Maurice LaMarche) is a buff member of the Foot Clan who works alongside Foot Lieutenant. • Jocelyn (voiced by
Cree Summer) is a Foot Initiate who gains the mark of the Foot in "How to Make Enemies and Bend People to Your Will". Foot Recruit claimed to Baron Draxum that she got the mark because her parents are "big donors". • Foot Soldiers (various voices) are an army of ninjas that are associated with the Foot Clan. • Origami Ninjas – Ninjas made out of paper that is created by Foot Lieutenant and Foot Brute. •
Krang are parasitic aliens who invaded Earth a long time ago but were defeated and banished to another realm. When the Foot Clan came under attack, the Krang gave Oroku Saki the Dark Armor, which eventually consumed his soul and turned him into Shredder. Only three of them managed to survive by the time they were freed, one was their leader who was banished again by Leo, the other was a female warrior with a temper who was captured by humans and the third one who's mute was in charge of bringing the Technodrome and controlling it who was apparently destroyed with it. •
Krang One (voiced by
Jim Pirri) is the leader of the Krang. • Krang Two (voiced by
Toks Olagundoye) is a sadistic and temperamental member of the Krang. • Krang Three - A silent member of the Krang. • Huginn (voiced by
Timothy Simons) and Muninn (voiced by
Sam Richardson) are two small
gargoyles with retractable wings that are often seen sitting on Baron Draxum's shoulders. Huginn has a frog-like body and a cat-like head and tail while Muninn has a frog-like body and a tapir-like head. Their names and presence as Draxum's companions are a play on
Odin's ravens
Huginn and Muninn. • Garm and Freki (both voiced by
Fred Tatasciore) are two guardsman warriors who work for Baron Draxum and are experts at armed combat. They can also ride giant demon-like dogs. In "Repairin' the Baron", Garm and Freki are offered forgiveness from the Council of Heads if they bring Draxum to the Hidden City to stand trial for his crimes. They are later mentioned by Draxum to Raph and Mikey to be bounty hunters who work for whoever has the most money. Their names are a play on the wolf monster
Garmr and Odin's wolf
Freki. • Oozesquitos are a swarm of mutant
mosquitoes that are often used by Baron Draxum. They store mutagen in their abdomens to inject anyone they bite which turn them into mutants. • Mutant
Silverfish are a bunch of mutant silverfish. If they are attacked, the Mutant Silverfish will split into smaller silverfish that would later aggregate back to their original state. • Rupert Swaggart / Meat Sweats (voiced by
Johnny Rotten • Albearto (voiced by
Tom Kenny impersonating
Ed Wynn If cut in half, Warren can regenerate. Since his mutation, he declared himself the greatest foe of the Teenage Mutant Ninja Turtles always ignore him. Warren Stone later gains a gauntlet that can shoot beams which he named Charlotte. This was later found to be one piece of the Kuroi Yoroi, which was needed to revive Shredder. In "Warren & Hypno, Sitting in a Tree", Warren has become a roommate of Hypno-Potamus and loses the gauntlet to Baron Draxum. While heavily implied in the show but not outright confirmed, social media posts from writer Russ Carney and executive producer Andy Suriano confirmed that Warren and Hypno-Potamus are a couple. • Mezmer-Ron / Hypno-Potamus (voiced by
Rhys Darby) is a successful stage magician and hypnotist who mutated into a
hippopotamus after he was stung by an Oozesquito, merging him with his pet hippopotamus Doug. Driven by envy, Hypno-Potamus strives to outachieve any magician with an even greater "trick" than they can produce, and find a way to bring Doug back to life, leading to his clashes with the Teenage Mutant Ninja Turtles. In "Warren & Hypno, Sitting in a Tree", Hypno-Potatmus has become a roommate of Warren Stone, later being captured by Baron Draxum in an attempt to lure Warren and the turtles to him so Draxum could capture them and take Warren's gauntlet - a plan that Hypno took part in in order to secure Warren's safety. However, once it was revealed that Draxum had no real intent to keep Warren safe, Hypno temporarily sided with the turtles - resulting him saving Warren's life and the two leaving peacefully. While heavily implied in the show but not outright confirmed, social media posts from writer Russ Carney and executive producer Andy Suriano confirmed that he and Warren Stone are a couple. • Repo Mantis (voiced by
Fred Tatasciore) is the vicious, treacherous, and greedy owner of a
salvage yard called Repo Mantis Salvage who was mutated into a purple mutant
mantis after being stung by an Oozesquito. His mutation has not affected his salvaging business. • Mrs. Nubbins is Repo Mantis' pet cat who was stung by an Oozesquito and mutated into a cat/mantis hybrid due to having been in contact with her owner. Repo Mantis keeps Nubbins locked up for his own safety. • Ghostbear (voiced by
Jorge Gutierrez) is a human masked wrestling champion in a white bear cape who cheats. Raphael was a fan of him until he learned the truth about his fighting techniques. In "Snow Day" while trying to get revenge on the Turtles for ruining his pro wrestling career, Ghostbear is stung by a defrosted Oozesquito and mutated into a mutant
polar bear. This new form gives him the ability to become intangible. • Mutant Cockroach Gang are an unnamed group of mutant
cockroaches that posed as mascots. • Atomic Lass (voiced by
Grey Griffin) is an unnamed mutant cockroach dressed as Atomic Lass. • Joey the Junkyard Dog (voiced by
John DiMaggio) is an unnamed mutant cockroach dressed as Joey the Junkyard Dog. • Robot Vampire (voiced by Grey Griffin) is an unnamed mutant cockroach dressed as Robot Vampire. • Sergeant Woodpecker (voiced by
Eric Bauza) is an unnamed mutant cockroach dressed as Sergeant Woodpecker. •
Baxter Stockboy (voiced by Ramone Hamilton) is an unpaid stockboy and self-proclaimed "internet celebrity". Both vengeful and avaricious, he strives to either profit from his
live-streamed schemes or take revenge on anyone (particularly the Turtles) who hinders him in doing so. • Mrs. Cuddles (voiced by
Eliza Schneider) is a plush rabbit character from the TV series of the same name who comes to life to feeds on the fear of her to become bigger and stronger. If someone laughs at her, Mrs. Cuddles loses her size and strength. • Big Mama (voiced by
Lena Headey) is a cunning
Jorōgumo who can change between her purple-skinned human form and her humanoid spider form and has a habit of using improper upper-class words when she speaks. She is the owner of an extradimensional gladiator arena called the Battle Nexus in the secret sub-level of the Grand Nexus Hotel, which she runs in her human guise. Big Mama uses the Oozesquitos in her possession to mutate anyone into mutants so that they can fight for her entertainment in the Battle Nexus. Her plot has brought her into conflict with Baron Draxum who felt that Big Mama was misusing the Oozesquitos. Hinted in "The Ancient Art of Ninja Hide and Seek", the episode "Many Unhappy Returns" reveals that Big Mama was the ex-girlfriend of Hamato Yoshi and the indirect cause of his mutation when she abducted him to fight in the Battle Nexus. • Gus (voiced by
Fred Tatasciore) is a mutant
bulldog loyal to Big Mama who can grow spikes on his body. • Fox Bellhop (voiced by
Eric Bauza) is an unnamed mutant
red fox who works as a bellhop at the Battle Nexus. • Octopus Elevator Operator (voiced by
Nolan North) is an unnamed mutant
octopus who works as an
elevator operator at the Grand Nexus Hotel. • Otter Bellhop (voiced by
Nolan North) is an unnamed mutant
North American river otter who works as a bellhop at Big Mama's Battle Nexus. • Owl Bellhop (voiced by
Fred Tatasciore) is an unnamed mutant
barn owl who works as a bellhop at Big Mama's Battle Nexus. • Battle Nexus Champions are a group of powerful fighters from the Battle Nexus. •
Troll is a troll with a lion-like head who wields a club. •
Sprite (voiced by
Zelda Williams) is a sprite who never laughs. She fights Leo and Carl Sando while possessing the
Statue of Liberty. Leo and Carl were able to defeat it by doing comical moves that she found funny. •
Amphisbaena is a two-headed serpent with an insatiable appetite. • Cortex (voiced by
Eugene Byrd) is a
Cthulhu-like creature with extremely high intelligence. •
Purple Dragons are a trio of snobby, criminal tech club students at April's high school. They are skilled at computer hacking, high-tech theft, and other technology-based abilities. • Kendra (voiced by
Tania Gunadi) is the leader of the Purple Dragons. She has known April since
kindergarten. In "Breaking Purple", it is revealed that Kendra's dad married Jase's mom, making them step-siblings. • Jase (voiced by
Eugene Byrd) - Member of the Purple Dragons. He has a fear of cats and dogs and, despite clearly being smarter and more sensible than Jeremy, is often regarded with disdain by Kendra. In "Breaking Purple", it is revealed that Jase's mother is married to Kendra's father, making them step-siblings. • Jeremy (voiced by
Kyle Massey) is an African-American member of the Purple Dragons. He refers to Kendra as "chief". • Sando Brothers are two acrobat brothers in a circus who were turned into mutant
crabs by Oozesquitos. They can attack by launching their left claws at their opponents. • Ben Sando (voiced by
Paul Scheer) is the first half of the Sando Brothers who has no hair. • Carl Sando (voiced by
Jason Mantzoukas) is the second half of the Sando Brothers who has hair. • Capitán Piel (voiced by Christian Lanz) is a living skin who is the brother of Señor Hueso and the pirate captain of the S.S. Alexis. His name is Spanish for "Captain Skin". • Kraken Pirate (voiced by
Eric Bauza) is a humanoid
kraken who is a member of Capitán Piel's pirate crew. • Mermaid Pirate (voiced by
Rob Paulsen) is a
mermaid who is a member of Capitán Piel's pirate crew. • Sea Serpent Pirate (voiced by
Maurice LaMarche) is a humanoid
sea serpent who is a member of Capitán Piel's pirate crew. • The Makers of Brutality are a gang of
ogres. • Boss Beverly (voiced by
Gillian Vigman) is a one-eyed ogre who is the leader of the Makers of Brutality. • Ogre Henchmen (voiced by Gillian Vigman) - The unnamed henchmen of Boss Beverly. • The Masters of Barbarianism is a gang of reptilian creatures. • Boss Bruce (voiced by
Vic Chao) is a humanoid
Japanese dragon with an eyepatch over his left eye who is the leader of the Masters of Barbarianism. • Snake Henchmen (voiced by
Eric Bauza and
Vic Chao) is the unnamed humanoid snake henchmen of Boss Bruce. • Dr. Alex Noe (voiced by
Tony Hale) is a
dentist obsessed with collecting teeth from extremely rare or unusual creatures. • Sloppy Joseph - When an Oozesquito in Baron Draxum's possession gets loose in the kitchen, he and April trap it in a pot. This causes the Oozesquito to mutate the
mystery meat concoction that Draxum made inside the pot to create a mutant that is named Sloppy Joseph (a pun on the term "
sloppy joe"). Sloppy Joseph can get bigger from every food that it consumes. • Scor-Pion (voiced by
John Kassir) is a
zookeeper who was stung by an Oozesquito and mutated into a mutant
scorpion after he was pushed into the scorpion habitat by his co-workers. Marcus Moncrief once mistook him for an alien. • Mud Dogs are a group of criminals operating in the Hidden City who mistook Raph as Heinous Green, all three of which are voiced by Donnie, Leo and Mikey's voice actors from the
2012 series. • Dastardly Danny (voiced by
Rob Paulsen) is the rat-like member of the Mud Dogs. • Loathsome Leonard (voiced by
Seth Green) is the ogre-like leader of the Mud Dogs. • Malicious Mickey (voiced by
Greg Cipes) is the
electric eel-like member of the Mud Dogs. • Heinous Green is a size-shifting green Yōkai who is one of the most wanted criminals in Hidden City. The Hidden City Police mistook Raph for this villain. • Kristoff van Bradford (voiced by
Peter Stormare) is a martial arts action star and Lou Jitsu's rival who took over most of Lou Jitsu's dojos and teaches his students to do dishonest martial arts moves. • Komodo Dojo Students (four of them voiced by
Jill Talley) are five students at the Komodo Dojo who are loyal to Kristoff. • Frank (voiced by
Eric Bauza) is one of Kristoff Van Bradford's students. • Komodo Dragon Yōkai is an unnamed
Komodo dragon Yōkai which can infuse anyone it bites with mutagen, endowing them with superhuman strength. It is loosely based on the character King Komodo from the
Image Comic series. ==Other==