Teenage Mutant Ninja Turtles is a 2015 American computer-animated web series.
When ninjutsu master Hamato Yoshi and his pet turtles touch the Mutagen (a chemical from another world that transforms anyone who comes in contact with it into mutant creatures), they undergo major physical transformations: Hamato Yoshi becomes a humanoid rat under the name of Splinter and the turtles become a humanoid turtles. Splinter retreats to the New York City sewers, where he raises the four turtles as his sons and imparts to them his knowledge of ninjutsu.
- Teenage Mutant Ninja Turtles - A team of anthropomorphic freshwater turtles who are the protagonists of the series:
- Leonardo - "Leo" is an enthusiastic ninjutsu student, learning how to be an effective leader for his three often unruly brothers. He wears a blue mask and fights with two katana swords called Niten Ryu.
- Donatello - "Donnie" is in charge of the design and manufacture of all of the tools and weapons in the Turtles' arsenal, and he is also a gifted hacker. He wears a purple mask and fights with a rokushakubo which converts to a naginata. He has a crush on April in this series and his brothers tease him about it. Raphael - "Raph" often lets his impulsiveness get in the way of rational thinking. He wears a red mask and fights with two sai.
- Michelangelo - "Mikey" loves video games, skateboarding, pranks and pizza. He wears an orange mask and fights with two nunchaku, which convert into kusarigama. Though he possesses a child-like innocence, Mikey always brings his best game to a fight.
- April O'Neil - The 16 year-old niece of Dr. Gordy O'Neil who likes to play video games and eat pizza.
- Splinter - Splinter was born a human named Hamato Yoshi and resided in Japan where he became an expert of ninjutsu. When his friend Oroku Saki sought the affections of Splinter's wife Tang Shen, Saki wished to discredit Yoshi in front of her. Yoshi lost his temper and the altercation ended their friendship culminating in a battle that burned down Yoshi's home killing Tang Shen and their daughter Miwa. After moving to New York City, Yoshi had just purchased four pet turtles when he stumbled upon an exchange in an alley between two Kraang droids. Seeking to silence Yoshi before he could share what he had seen, a fight ensued and the canister the droids had been carrying smashed open splashing both Yoshi and his turtles with an alien chemical called mutagen. As the result, Yoshi (having had contact with a rat upon entering an alley) changed into a humanoid rat. Realizing he could no longer live a normal life topside, Yoshi retreated to the New York sewers where he raised his pets as sons and taught them the ancient Japanese fighting art of ninjutsu.
- The Foot Clan - A ninja organization that is led by the Shredder.
- Shredder- One the main antagonist of the series and leader of the Foot Clan. Once friends with Hamato Yoshi (Splinter) in Japan, Oroku Saki (Shredder) and Splinter fight after Shredder falls in love with Splinter's wife, Tang Shen. A final battle results in a fire that burns down Hamato's home and kills Tang Shen and Hamato's infant daughter Miwa. Years later, Shredder learns that Splinter is alive and in New York after seeing the Hamato clan crest on a shuriken during a television news report. Seeking to finish his business with Splinter, Shredder and his Foot Clan relocate to New York. The Turtles first encounter Shredder in the fifth episode.
- Dogbite - Chuck Morris is a famous martial artist and secretly Shredder's apprentice as a member of the Foot Clan. Morris is sent to New York with Xever with orders to find Splinter. Morris and Hector go after the Turtles again and are exposed to mutagen. As Morris was previously bitten by Shredder's pet Staffordshire Terrier, Larry, the mutagen transforms him into Dogbite, a hideous, spike-backed dog-like mutant with a large hands, acute senses, and super poop
- Lizardface - Hector was an imprisoned Australian street thug until Shredder freed him and brought him into the Foot Clan. Shredder assigned Hector to assist Chuck Morris in finding Splinter. During a battle Hector is exposed to mutagen. As Hector was previously bitten by a komodo dragon, the mutagen transforms him into a violent lizard-like mutant with sharp teeth called "Lizardface".
- Spikewood - Spike was a Cockney street thug who was working for the Shredder. As Spike previously touched a dead tree, the mutagen transforms him into a Spikewood, a tree monster with a massive left arm that is covered with spikes.
- Thornshell - Bobby was a Texan rockstar who was modified by the D'robilians. It is because of this that Angie dumped Leo for Bobby until Stitch saved her from the Foot Clan. Bobby became intrigued with the mutagen that Leo hold it. Bobby gets mutated accidentally, turning him into a mutant turtle. Bobby is now furious that he has been transformed into a giant, hunchbacked turtle-like monster (with spikes on his back and shoulders). Consumed with hatred, he joins the Shredder to help him destroy Leo. He dubs himself "Thornshell" (with the mutation being contributed to a snapping turtle biting on Bobby's arm).
- Killershark - Killer was a Cuban thug who was working for the Shredder. As Killer previously bitten by a great-white shark, the mutagen transforms him into a Killershark, a muscular shark-like mutant with a large hands and feet, and a razor sharp teeth.
- Foot Ninja - The foot soldiers of the Foot Clan.
- Baxter Stockman - A technical genius and the scientist responsible for creating the mousers: a series of mouse-like robots that can eat through practically anything. While at first it appears the robots were created in order to help control the cities growing rat problem, it is revealed that Stockman created them as a technical resource for the Shredder. The Turtles first encounter Stockman in his rudimentary battle armor, while he attempts to break into a building. The Turtles defeat him, but Stockman obtains Donatello's T-Pod, which contains a military-grade artificial intelligence chip, and incorporates it into his battle armor. The next time the Turtles run into Stockman, his battle armor has upgraded itself. Eventually, the Stockman battle armor and the T-Pod merge into a destructive robotic being, which Mikey dubs "The StockmanPod." The StockmanPod makes quick work of the Turtles, causing them to flee. Using wisdom from Splinter about "fighting the person inside the armor," the Turtles engage the StockmanPod again, and make use of a simple beehive, to cause the StockmanPod to fall off a building. The Turtles deactivate the T-Pod and throw Stockman in the dumpster again. Following the incident with the M.O.U.S.E.R.S., Dogbite and Lizardface bring Stockman to Shredder. Shredder threatened to kill Stockman for interfering with his plan to kill the Turtles, but spares him and comments on how his intelligence could be useful.
- D'robilians - One of the main antagonists of the series. The D'robilians are a race of brain-shaped, squid-like aliens that pilot robotic bodies and who are responsible for bringing mutagen to Earth. They are the worst rivals and enemies of the Utroms.
- Batclaw - Bat was a thug who was working for the D'robilians as their getaway driver. The Turtles end up interrogating Bat for information on where the D'robilians are kidnapping April and Gordy O'Neil. When the Turtles find out where the D'robilians are kidnapping April and Gordy O'Neil, a truck full of mutagen that the Turtles send towards the D'robilians crashes into the base exposing Bat to the mutagen turning him into a lobster-like monster that Michelangelo dubs "Batclaw" (with the mutation being contributed by Bat being pinched by a lobster). When the Turtles were trying to rescue April O'Neil and her uncle from the D'robilians, they are attacked by Batclaw. Leonardo lures him into the vicinity of a power core where Batclaw is electrocuted and blown up. After the Turtles left, however, Batclaw's heart started beating again.
- Platypus-vion- Colonel Meister was a wealthy scientist who works for Batclaw. During a battle with the D'robilians, he was splashed with mutagen and turns into a platypus hybrid (the mutation being conributed to a platypus coming in contact with him).
- Bullhead - Bull Von Screechienz was a German loan shark who was working for the D'robilians. During a battle Bull is splashed with mutagen and transforms into a giant Minotaur-like monster who Michelangelo dubs "Bullhead" (with the mutation being contributed to a bull attacks Bull).
- Dr. Gordy O'Neil - A scientist who is April O'Neil's uncle.
- Leatherhead - Leatherhead is an alligator that was originally owned by a young boy until he died in a car accident and Leatherhead fall into a storm drain, where he was taken in by the Utroms when they discovered that their mutagen (the same that transformed the students into the Turtles) made him sentient. Leatherhead lived with the Utroms peacefully until Shredder's attack forced him into hiding. Some time later Baxter Stockman fooled him into aiding him with a scheme to restore his body. Ultimately, Leatherhead learned that Stockman had ties to the Shredder and wound up fighting on the side of good. As the series progresses he becomes a semi-regular member of the Turtles extended family. He is shown as a friend of Angie Kittypaws and the Turtles.
- Angie Kittypaws - The 16 year-old African American girl, a popstar singer and a karate student who is Leo's romantic love interest, sweetheart and girlfriend and Baxter Stockman's stepdaughter. She is a damsel-in-distress. She also wears a sleeveless white shirt mostly hidden under a pink hooded jacket and a white skirt. She loves kittens, Space Heroes movie, video games, and pizza. As Angie previously pets her pet white kitten, she was injected by her stepfather Baxter Stockman with a mutagen who fooled Leatherhead. She transformed into a white cat-like mutant. She truly belongs with Leo as his true love.
- Dr. Tyler Rockwell - Dr. Tyler Rockwell was a scientist. He and his partner Baxter Stockman were approached by the Foot Clan to work on an experiment that involved mutagen, a neurochemical, a modification and gorilla DNA. A news report mentioned that Dr. Rockwell was missing. April and the Turtles discovered that Stockman with chemicals that transformed Rockwell into a gorilla-like mutant that can read emotion. Ultimately, Rockwell learned that Stockman had ties to the Shredder and wound up fighting on the side of good. As the series progresses he becomes a semi-regular member of the Turtles extended family. He is shown as a friend of April and the Turtles.