Characters / Teenage Mutant Ninja Turtles (2003)

Characters as they appeared in, and characters exclusive to or making their debut in, the 2003 4Kids-produced TMNT cartoon. For tropes relating to characters who originally appeared in other incarnations or were created here and went on to appear elsewhere, please visit the franchise character page.

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The main heroes group. The TMNT with their master, Splinter.

As a whole

  • Airplane Arms: The turtles consistently run like this.
  • Badass Family: The turtles and Splinter, undeniably so.
  • Bald of Awesome: By virtue of being hairless reptiles.
  • Color-Coded Characters: In the Mirage comics, the Turtles all wore red bandanas (not that it mattered much in a black-and-white comic), leaving their distinct weapons as usually the best way to tell them apart. The series follow the '87 choice of give Leonardo blue, Donatello purple and Michaelangelo orange, while Raphael kept red. Lampshaded in Turtles Forever when the Mirage Turtle call "silly" both the '87 and 2003 versions for this.
  • Five-Man Band: The Turtles including their allies
  • Foil: All four of them as a group and in pairs
  • Four-Temperament Ensemble: Leonardo the phlegmatic, Donatello the melancholic, Raphael the choleric and Michaelangelo the sanguine.
  • Future Badass: Leonardo, Raphael, April, and especially Mikey, in "Same as it Never Was".
  • Happily Adopted: The Turtles love and respect Splinter as if he were their real father.
  • Highly Visible Ninja: They can frequently be seeing putting around on a blimp. With a giant "Turtles" on it.
    • Not to mention the Turtle Van, which was customized with armored plates resembling turtle shells and laser turrets on the roof.
  • Know When To Fold Them: The Turtles sometimes invoke this, with Raph on one occasion settling on a "tactical retreat". This is also the Ancient One's first lesson, when a bitter Leo faces a losing battle against intangible demons.
    Leo: To surrender is not the warrior's way!
    The Ancient One: You won't be much of a warrior without a head!
  • Metamorphosis: From turtles to humanoid turtles.
  • Named After Somebody Famous: They are all named after iconic Renaissance artists.
  • Ninja: They are ninjas.
  • Trademark Favorite Food: Though pizza is the favorite food of all four turtles, Michelangelo eats it more obsessively than the other three.
  • True Companions: Badass Family plus friends.
  • Undying Loyalty: The turtles to Splinter.
  • Weirdness Magnet: Noted several times:
    Michelangelo: How come all the weird stuff always happens to us? I mean, we were just minding our own business, when WHAM, that time lady fell out of the sky, right on top of us! Now we're stuck here AND we've gotta go to that creepy-loking place! It just doesn't seem fair!!!
  • Would Hit a Girl: The Turtles have no problems with attacking Karai, although to be fair, she is more than capable of holding her own in a fight.


The leader. In this version, he is more well-balanced and serious than in the 1987 TV series and first three films. Like the Mirage comics and the film pentology, Leo and Raphael have disagreements constantly, particularly in the City at War trilogy.

  • The Ace
  • Authority Equals Asskicking: Consistently the most skilled Turtle, he falls into the leadership role by default.
  • Badass Longcoat: In "Same As It Never Was".
  • Big Brother Instinct: Even though he's never officially stated to be the oldest.
  • The Chains of Commanding: Michaelangelo actually notes this in an episode of the 4Kids series: Leo takes the burden of being the leader so his brothers can do what they want: Dontaello's free to pursue his technological inventions, Raphael's free to let loose and fight, and Mikey's free to just relax because their brother's in control.
  • Character Development: Really beautifully put into the mix in season 4 where Leonardo becomes the best fighter of the bunch while trying and failing to master his anger and fear after being defeated and stabbed in season 3.
  • Cultured Warrior: If one of the turtles is going to be in touch with Japanese traditions, it's gonna be Leo.
  • Deconstruction: A minor one but in Samurai Tourist, Mikey—yes, Mikey— gives an accurate analysis as to why Leo takes the burden on being the leader: so that he lets his brothers be themselves.
    Mikey: I think you all [Donatello, Raphael and Casey] should just lay off the poor guy [Leonardo]. I mean, it can't be fun always being the responsible one. And we're the ones who really benefit: Raph's free not to think cause Leo does all the thinking for him, Don's free to dream, and I'm free to take it easy all because Leo's busy being responsible enough for all of us.
  • Determinator
  • Dual Wielding: He always wields two swords, and if one is broken he still fights with the other one.
  • Emotions vs. Stoicism: A lot of what he puts up with has him wondering if he should fight or remain still.
  • Heroes Prefer Swords: As the leader of the group, Leo gets the shiny swords.
  • Heroic B.S.O.D.
  • Heroic Spirit: A big reason why he's a determinator.
  • He's Back: Happens to Leo twice: First during "Return to New York", when he confronts the Foot Elite which nearly killed him during their first encounter, and again in "Prodigal Son", the conclusion to his season 4 character arc.
  • Heterosexual Life-Partners: With Miyamoto Usagi.
  • Katanas Are Just Better: Obviously. Although Leonardo's swords are often much more closely modeled around the ninjato.
  • Knight Templar: Leonardo's story arc in the 4th season have him nearly cross over into Knight Templar territory. His rage gets so bad he actually wounds Splinter and has to be sent away to Japan to learn from Splinter's master.
  • Master Swordsman: He uses his katana very skillfully.
  • My God, What Have I Done?: Leonardo has an example of this in "The Ancient One", when he loses control and injures Master Splinter. Although he doesn't actually say the line, the look on his face after it happens and his subsequent remorse show he was clearly shocked, and deeply regretted his actions.
  • No-Holds-Barred Beatdown: He gets into quite a few of these. If he's not on the receiving end, he's usually administering it.
  • Red Oni, Blue Oni: The blue to Raphael's red.
  • Samurai: Leonardo is technically a ninja, but a lot of the tenets he quotes are in line with samurai. It's no surprise he and Usagi got along swimmingly.
  • Scars Are Forever: To an extent. In the Season 3 finale, Karai—whether accidentally or not—stabs Leo. Her sword goes through his shoulder and out the side of his upper shell. All throughout Season 4 the crack in his shell remains as he descends into Knight Templar territory, and even after he recovers it refuses to heal. Not until the Fast Forward reboot, anyway.
  • Sliding Scale of Idealism vs. Cynicism: He starts out at the very end of the Idealism scale, even believing the best of the Shredder and then his daughter Karai. As the seasons progress he shows signs of being capable of sliding down the other way—he does this in the fourth season—though he remains mostly rooted in idealism.
  • The Spartan Way: Leonardo as a child was suffering from a fear of heights. Splinter brings him to the top of a gigantic reservoir and pretends to be in danger of falling. Leonardo forces himself to crawl out and save him, and apparently conquers his fear in the process.
  • Took a Level in Badass: In the first season he can barely handle fighting one of the Foot Elite, and is nearly killed trying to take on all four. By the end of the fourth season, he not only takes on all four without apparent difficulty, but also bests Karai, the incumbent Shredder, in the process.
  • Took a Level in Jerkass: During the first half of the fourth season, combined with Heroic B.S.O.D.. He had a really good reason.
  • Weapon of Choice: Twin Katana.
  • What the Hell, Hero?: In a reverse from usual situation, Raph calls Leo out in 'The Ancient One' for injuring Master Splinter when Leo loses control in a fit of rage.
    Raphael: Leo, what the shell is your problem?!
  • Wrecked Weapon: Done to Leonardo's swords in the episode "The Shredder Strikes Back, Part 1", as the climax to the ass-kicking the character gets in that episode. And again in "Big Brawl, part 1" by a Gom-Tai.

Voiced by: Sam Riegel

Donnie is still the smartest turtle like all of his incarnations. Like the other turtles except for Raphael, he loves the future for its new technology and gadgets.

  • Adorkable
  • Badass Bookworm: He's an Omnidisciplinary Scientist par excellence as well as a skilled warrior.
  • Badass in Distress: The time he was captured by the Triceratons, and the end of the Outbreak arc after being mutated a second time. Less dramatic instances are scattered throughout the 4Kids series, too, usually when it would be easy for him to solve a problem/end an episode before its time.
  • Badass Pacifist
  • Beware the Nice Ones
  • Beware the Quiet Ones
  • Big Little Brother: Taller than Leo but, fittingly, tied with Raph.
  • Bond Breaker: Donatello was warped into an alternate future where he had disappeared for 20 years. Without his resourceful, tech savvyness, the Turtles were disbanded and the Shredder had succeeded in world domination. The supporting cast made up the last rebel resistance.
  • Fighting from the Inside: A variant while he was prisoner on board the Triceraton mother ship, resisting against borderline Mind Rape. He held out for awhile, but needed help to fend the assault off.
  • First-Person Smartass: Whenever he's the one voicing the opening narration.
  • Future Me Scares Me: One episode of the Fast Forward season has a future journal suggesting that robot butler serling might be Donatello's future self. Donnie and his brothers are grossed out by the idea. Fortunately, the journal is a fake set to discourage the turtles from trying to learn too much about the future.
  • Gadgeteer Genius: Considering that he's self-taught, living in a sewer, and working mostly with scavenged junk, Don's inventing abilities are downright super-reptilian.
  • Genius Bruiser
  • Gentleman Snarker: He's second only to Splinter where polite snarking is concerned.
  • Heroic B.S.O.D.: Like Leonardo, he suffers one in the 4Kids series' last season up until the end of episode 5. Cody finally manages to fix his Time Window to send the turtles and Splinter back to the present, but due to some inteference from Viral, Splinter is vaporized and it's later revealed that he's trapped in cyberspace.
  • Intelligence Equals Isolation: Not often, but on occasion he's sequestered off in his lab. Most noticeable in 'Return to the Underground'.
  • The Klutz: A trait that doesn't come up often— but if/when it does, it's always in the middle of a fight or stealth mission.
  • Lovable Nerd
  • Metamorphosis: Twice— once in the backstory, once at the end of the fourth season.
  • Mr. Fixit
  • Nice Guy
  • Omnidisciplinary Scientist: He's a genius mechanic, but usually also has knowledge of biology.
  • O.O.C. Is Serious Business: Played backwards, actually. We get the 'serious business' part within the first few minutes of Same as it Never Was. Just before the episode's Bittersweet Ending, the OoC part comes in.
  • Out-of-Character Moment: Don absolutely slaughters Ch'rell at the end of SaiNW, a far cry from his usually pacifistic actions. Understandable, of course given the circumstances.
  • Precocious Crush: He has one on April.
  • The Professor
  • The Reliable One
  • Resist the Beast: Happens to Donatello in "Adventures in Turtle Sitting". He even begs April and Casey to "stay away from" him as he runs off, before he mutates fully and starts to attack them.
  • Sesquipedalian Loquaciousness: Donatello, being the smart turtle, is particularly fond of this. A notable example is in "The Shredder Strikes Back, Part 1", when he and Raphael are watching a football match on television.
    Raphael: 'Panthers', 'Rams', 'Bears', they even got 'Dolphins'. You'd think they'd have room for something a little more...reptilian.
    Donatello: The 'Turtles'? My friend, unfortunately the lowly turtle has been saddled by society with the stereotype of being velocity challenged.
    Raphael: Say what?
  • Teen Genius
  • This Is Unforgivable!: In "Same as it Never Was", after stating a Big "NO!" upon watching the Karai Legions kill Future Mike to his horror, Don gets pushed too far. His response? "You'll pay for this, Shredder! If it's the last thing I do, YOU WILL PAY!"
  • Weapon of Choice: Simple Staff.
  • Weirdness Magnet: Even amongst his brothers.
  • Wrong Genre Savvy: Demonstrated a couple of times — like trying something he saw in a movie during a fight with the Foot. It doesn't work.
  • Wrecked Weapon: Donatello's bos were constantly getting broken. One wonders why he never upgraded to a steel pole or something a bit sturdier.

Voiced by: Frank Frankson

Raphael's personality is more like his original incarnation—he is angrier and more sardonic, but not quite as violent (although he is still impulsive). One incident emphasising his quickness to anger is where he almost smashed Michelangelo's head in with a pipe is shown here. In this carnation Raphael talks with a similar Brooklyn accent used in the movies.

  • Aloof Big Brother: Partially inverted. He's younger than Leonardo making him an aloof little brother, but older than Donatello and Michelangelo, playing it straight for them.
  • Badass Biker: He is shown to be a skilled motorcyclist and has his own motorcycle, the "Shell Cycle".
  • Bash Brothers: With Casey.
  • Berserk Button:
    • He loves his bike and quickly turns to rage if anyone messes with it.
    • Did we mention how much Raph hates bugs? In "April's Artifact", he gets pushed too far after recovering from the paralysis given to him by one of the hornets, declaring in a Punctuated! For! Emphasis! fashion that bugs must pay.
  • Big Brother Bully: To Mickey.
  • Big Damn Heroes: In the "City At War" arc (with some help from Splinter).
  • Brooklyn Rage: Not only because he's an angry New Yorker - the first movie even gives him a Brooklyn accent.
  • Catch Phrase: "I got your X right here." and also "You and me are having words."
  • Deadpan Snarker: To the point where he should be the picture for the trope.
  • Driven by Envy: Downplayed. Raphael appears to live in the shadow of Leonardo and resents his brother's social position in the group. However, though at times he may seem quite jealous of Leonardo, Raphael's rivalry with him is heavily toned down in comparison to the comic books, and Raphael rarely shows a deep hatred towards Leo as the series progresses.
  • Fire-Forged Friends: With Casey
  • Hair-Trigger Temper
  • Heel Realization: In "City at War part 3".
  • Hot-Blooded
  • Jerk with a Heart of Gold: He's more abrasive than the others, but is still as noble as the other Turtles.
  • Jerkass Façade
  • Jerkass Has a Point / What the Hell, Hero??: Raph's attitude during the "City at War" trilogy. What the Hell, Hero? stems from the fact that he refuses to believe that the Turtles were responsible for New York's gang war between the Foot Clan, Purple Dragons, and the Mob and he sounds like he doesn't care about the innocent people who have been caught in the crossfire. This stems from his statement that the Turtles' involvement would only "add fuel to the fire", in other words, make the situation worse and to be honest, Raph wasn't wrong; apart from Leo saving a gang of mobsters from an exploding warehouse and evacuating a man trapped in a bus, the Turtles weren't making much progress to end the war until Karai showed up and offered a truce.
  • Middle Child Syndrome: Played with. Raphael isn't the middle turtle, but he feels as if no one understands him.
  • Number Two
  • Red Is Heroic: He's always a hero but typically in on-going series he plays the lancer to Leo while in one-off stories he is the main protagonist who has to overcome this anger.
  • They Really Do Love Each Other: Despite sometimes being a jerk to his brothers, Raphael is very protective of them.
  • This Is Unforgivable!: Raph doesn't take too well to having been paralyzed by one of the hornets in the episode "April's Artifiact".
  • Throwing Your Sword Always Works: Raph throws his sai a lot.
  • Took a Level in Kindness: It's more so "losing a level in jerkass", but by Back to the Sewers, Raph was no longer beating up Mikey or challenging Leo's authority, though he still flung a few insults here and there and even those were reduced.
  • Weapon of Choice: Sai Guy.
  • What the Hell, Hero?: In "Meet Casey Jones", Leo and Don call Raph out when he loses his temper and almost attacks Mikey with a metal pipe.
    Leonardo: Raphael! Have you lost your mind?!
    Donatello: You OK, Mikey? What were you thinking, Raph?!
  • Why Did It Have to Be Snakes?: A running gag throughout the world of TMNT is Raphael's fear of bugs (entomophobia). However, in this carnation, it is less a phobia, and more of an intense hatred and disgust
  • You Have Got to Be Kidding Me!: Raph loves using this.

Voiced by: Wayne Grayson

Known as "Mikey" to his brothers, his personality is more akin to the Mirage comics than the 1987 TV series. Still the comic relief, he often makes statements that spoof pop culture, although he uses less surfer language than in the 1987 cartoon series. His trademark nunchaku are once again his primary weapons, but he has used other weapons such as grappling hooks and those of his brothers.

  • Arbitrary Skepticism: Michelangelo is the first to encounter Leatherhead, and when he tells them, the rest of the Turtles disbelieve him. At this point in the series, they have already encountered/know the existence of ninjas, criminal organizations, superheroes, cryptids, aliens, and mystical forces, yet a giant crocodile (mutated in the same way they were) is unbelievable.
  • Attention Whore
  • Badass Adorable: Silly, loves him some comic books, childish, always willing to crack a joke and and can kick tons of asses with his nunchucks.
  • Beware the Nice Ones
  • Beware the Silly Ones
  • Big Eater: He'd often annoy his brothers by eating all the pizza.
  • Brilliant, but Lazy: He's usually portrayed as having great potential, but because of his more laidback personality, he'll focus on something more fun instead.
    • This is enforced with his Weapon of Choice (the chucks, see below), the laziest of the turtles is the one wielding the most complex and difficult weapon. That's not something one can do without a gift for it.
  • Butt Monkey: If any of the Turtles klutzes out or has something bad happen to them for comic effect, it's Michelangelo.
  • Catch Phrase: The most famous "Cowabunga!"
  • Character Development: Michelangelo finally grows up, begins to use his innate skills to his full potential, and proves his worth as a thoughtful member of the team.
  • Cloudcuckoolander: Generally the most whimsical of the turtles.
  • Crouching Moron, Hidden Badass: In Michelangelo's first centric episode, he becomes a superhero, saves another superhero, and during all this learns a lesson on why he's a ninja: because it's what he does best.
    • In "Touch and Go", Splinter tells him that he is the most naturally athletic of his brothers and he is crowned the winner of the Battle Nexus on a technicality (although with Leo's training, he wins outright in "Grudge Match").
  • Friend to All Living Things: He has had several pets in the past, including his pigeon Pete and his parrot Ditto.
  • Fun Personified
  • The Heart: Although he exasperates his three brothers on a constant level, when a serious rift between their bond takes place, he usually is the one to try and patch things up...usually via humor.
  • Hidden Depths: In spite of being the laziest of the Turtles, he's the one with two of the weapon that's the most difficult to master. He's also surprisingly introspective and sometimes analyzes the nature of his brothers.
  • Hooks and Crooks: He uses one briefly as a callback to precendent show.
  • Jumped at the Call
  • Keet
  • The Knights Who Say "Squee!"
  • Large Ham
  • Leeroy Jenkins: He doesn't usually think of a strategy before heading into battle.
  • Nice Guy: Generally is the most friendliest, most outgoing and most soft-hearted of the Turtles. However, sometimes, he borders on AdaptationalJerkass).
  • Plucky Comic Relief: He got this role in the show and held onto it throughout all other incarnations.
  • Pungeon Master: Michelangelo, much to his brothers' continued annoyance. He constant puns almost always trigger negative reactions from his brothers, ranging from groans, Facepalms, and derogatory looks, to outright physical punishment such as head-slaps, flicks and pulling the ties of his ninja mask. His brothers aren't immune to it either: on the rare occasions when one of them says a bad pun they'll almost always get a similar Lame Pun Reaction from another turtle, though it's typically not as aggressive as the reactions dished out on Mikey.
  • Real Men Wear Pink: In Back to the Sewers he was positively delighted when April asked him to be her Maid of Honor, when people tried to call him the more gender-neutral "Turtle of Honor" he would correct them.
  • Screams Like a Little Girl
  • Secret Identity: Turtle Titan.
  • The Slacker
  • Surfer Dude: Less compared to Fred Wolf cartoon.
  • Unsportsmanlike Gloating: Michelangelo's preferred method of handling victory.
  • Weapon of Choice: Fighting with Chucks.

Voiced by: Darren Dunstan

Splinter is the adoptive father of Leonardo, Raphael, Donatello, and Michelangelo. He raised them and taught them in the art of Ninjutsu. He is portrayed as a dark gray rat in monk's robes and is stated to weigh 90 lbs.

  • Adaptation Dye-Job: Splinter's fur is turned gray for this series.
  • Adventure Rebuff: Splinter tries this several times, unsuccessfully.
    Splinter: How many times have I told you not to sneak out to the surface?
    Michelangelo: This month?
    Donatello: Five hundred and twelve, actually.
  • Badass Grandpa: He's much older than the Turtles, but is still a capable fighter when he needs to be.
  • Big Good: He and the Ancient One take up the role in the back half of the fifth season.
  • Bow and Sword, in Accord: Splinter is armed in this manner in the first episode of the "Exodus" two-parter.
  • Butt Monkey: He sometimes finds himself on the receiving end of his sons' antics.
  • Cool Old Guy: Sometimes joins the Turtles in their pastimes.
  • Deadpan Snarker: Fans tend to agree that he has some of the best lines in the show.
  • Elemental Rock-Paper-Scissors: How Splinter defeats the Foot Mystics during their initial battle.
  • Gentleman Snarker
  • Gratuitous Japanese: Splinter will occasionally use this.
  • Koan: Splinter is fond of these. Subverted on one occasion when he had to explain what he was saying.
    Splinter: Remember, my sons, even the mighty oak bows before the raging storm winds.
    Mikey: Huh?
    Splinter: Be careful and do not become overconfident!
  • Not So Above It All: He loves his soap operas, beats out Casey and Raph in poker several times, snarks periodically about his sons' antics, and even cracks a joke here and there.
  • Old Master
  • Offhand Backhand: When the Shredder and the Foot Ninja attack April's antique shop, Master Splinter smacked a Foot Soldier with his stick without even turning back. He does this again to another Foot ninja when Karai invades the Lair and maybe once more at one point in between.
  • Overprotective Dad: Not just towards the turtles but also towards April, Casey, and Cody (who also has Serling).
  • Papa Wolf: He will not take kindly to anyone who harms his four students.
  • Parents in Distress: For all of the times Splinter has rescued his sons, he has to be rescued by them often as well.
  • Rodents of Unusual Size
  • Simple Staff
  • Sophisticated as Hell
  • Team Dad


April O'Neil
Voiced by Veronica Taylor

April O'Neil is an ally and big sister/motherly-figure to the Teenage Mutant Ninja Turtles.

  • Adaptation Dye-Job: April's hair is given a purplish tone.
  • All Girls Want Bad Boys: April is shown to have an attraction to Casey Jones, though their contrasting personalities often make them bicker.
  • Badass Bookworm
  • Bare Your Midriff: April initial outfit includes this, and is in fact apparently considered appropriate attire for her job as a lab assistant.
  • Battle Couple: With Casey, eventually.
  • CoolBigSibling: April and Casey, who are 23 and 24, respectively, at the start of the series, are this to the teenaged turtles, who're supposed to 15 at the start of the series and about 18 or 19 at the end.
  • Hot Scientist: Just as in the Mirage comics, April started out as a 23-year-old science assistant to Dr. Baxter Stockman before he went openly evil.
  • Leitmotif
  • Letting Her Hair Down: Inversion: If April's hair isn't in her trademark bun the situation generally isn't good.
  • Mission Control: This version of April makes much more use of her scientific expertise and she often uses her computer skills to aid the Turtles.
  • Not So Above It All: Most notably in "April's Artifact" where she gets waaay into the Jungle Princess role and "The Christmas Aliens" where she sticks a spoon on her nose and grins stupidly.
  • Took a Level in Badass: In season 3, when Splinter teaches her martial arts.
  • Unfazed Everyman: After her intial scream and/or faint upon meeting the turtles she becomes this.
  • Waif-Fu: April sometimes demonstrates martial arts skills, after being trained by Splinter.

Casey Jones
Voiced by Marc Thompson

Casey Jones is a hockey-masked vigilante who fights crime at night.

  • Badass Normal: The only member of the team who has never had any mutant powers or abnormal origins in any continuity.
  • Bash Brothers: With Raph.
  • Battle Couple: With April.
  • Batter Up
  • The Berserker: Initially.
  • Big Damn Heroes: Gets to do this occasionally
  • Boisterous Bruiser
  • Brooklyn Rage
  • Catchphrase: It's revealed that the young turtles were teaching him all about martial arts and fighting (although they never found out) and each took turns to teach him what they knew. The cry comes from when Mikey was training him and told him to say "Gorogoro-sama!" (translation: Lord Thunder). But since Casey couldn't pronounce it correctly, he made his famous phrase.
  • Combat Pragmatist: Even the bad guys admit that Casey just plain fights dirty.
  • CoolBigSibling: April and Casey, who are 23 and 24, respectively, at the start of the series, are this to the teenaged turtles, who're supposed to 15 at the start of the series and about 18 or 19 at the end.
  • Dark and Troubled Past: Casey's hatred of crime is rooted in this incarnation in his childhood. While Casey was still a kid, his father Arnold Casey Jones, Sr. refused to pay protection money to the Purple Dragons. His father's shop was burned down as a result, and a teenage Hun threatened Casey to tell his father to pay up next time. Despite being threatened not to, Jones, Sr. subsequently went to the police, but with no success; it is implied that the Purple Dragons later killed him for trying to turn them in.
  • Embarrassing First Name: Arnold. Casey is his middle name, nickname, or derived from his middle initials (K.C.) depending on the incarnation.
  • Fire-Forged Friends: His friendship with Raphael consistently begins this way, and leads him to befriending the other turtles.
  • Good Is Not Nice: In his debut episode. He gets better though.
  • Heroes Want Redheads: Casey Jones with April O'Neil. The series even takes their relationship all the way as by the final season, they get married. April herself was much more of an obvious redhead than any previous incarnation as well.
  • Improbable Weapon User: Hockey sticks, baseball bats, golf clubs, croquet mallets, cricket bats...
    • The last being really amazing because you gotta know what a crumpet is to understand cricket!
  • I Know Madden Kombat: Casey uses sports equipment as his main weapon.
  • Jerk with a Heart of Gold: All versions have him being a jerk to at least one of the heroes, but they all still have a heart.
  • Leitmotif
  • Mask Power: When going into action, Casey usually wears an old-style hockey mask.
  • Overshadowed by Awesome
  • Took a Level in Badass: Casey undergoes a bit of this in Back to the Sewer when training under Master Khan (he manages to sneak attack and take down all four of the Turtles in this episode) but brainwashing is involved and the show doesn't give any strong indication of whether he retained his newfound fighting skills afterwards.
    • However, Casey still applies to this trope as it was revealed that when he was young, Casey lacked the confidence he shows as an adult, until the Turtles trained him to be assertive.
  • Vigilante Man: As he grew older, Casey became a vigilante and started hunting down crooks — particularly Purple Dragons — in the streets. until he meet Raph.
  • You Gotta Have Blue Hair: Has black-blue hair.


Voiced by F.B. Owens (Season 2-3), Gary Lewis (Season 4-BTTS)

An ally to the turtles with a scientific mind like Donatello and is often referred to as "LH.".

  • Adaptational Intelligence
  • The Berserker
  • Emotional Bruiser: This versionn was quick to show off just how tender-hearted he is in addition to how tough he is.
  • Genius Bruiser: Here he is not only intelligent but also well versed in various technical and scientific fields and therefore the Turtles and their friends (including Professor Honeycutt) find not only his giant strength but also his great intelligent helpful.
  • Metamorphosis: From alligator to humanoid alligator everywhere else.
  • My God, What Have I Done?: Leatherhead says this almost word for word when he attacks Michelangelo in a fit of uncontrollable rage, leaving him unconscious and fearing him badly hurt/dead. Don't worry though; Mikey was fine.
  • No-Holds-Barred Beatdown: In "Exodus, Part I", Leatherhead finally comes face to face with the Shredder. Enough said.
  • Sewer Gator: He was a pet alligator that was flushed into the sewers before he was mutated.
  • Unexplained Recovery: Hun and Leatherhead both appear to fall to their doom in "Exodus, Part 1". They both appear later with no explanation of how they survived or what happened to them immediately after the episode. Granted, their fall was indoors and it is rather hard to determine how far they fell (and unlike the Gyoji, it is rather doubtful that the writers intended this to be their death).
  • You Can't Go Home Again: Leatherhead initially yearns to rejoin the Utroms.

Professor Honeycutt/The Fugitoid

Voiced by Pete Zarustica

A scientist whose mind was accidentally transferred into a robot's body, and is forced on the run by groups who would use his inventions for their own purposes.


Voiced by

An apprentice "Timestress" whose job it is to oversee and protect the timestream.

  • Character Development: She's largely much less of a whiny jerk in her second appearance, due to having gotten some experience with the Time Scepter.
  • The Ditz: Renet is shown to be quite a scatterbrained person who came to her friends with good intentions, but with little practical skill she caused some problems across space and time.
  • Forgotten Phlebotinum: She's completely and inexplicably absent from the Fast Forward season, where the Turtles are stuck in the future — because if she'd appeared she could instantly have fixed their predicament.
  • Most Common Superpower: She is notably endowed as well.
  • Nice Job Breaking It, Hero!: Already in her first appearance, Renet was sentenced to dusting in Lord Simultaneous library because she had accidentally reversed the evolution on a planet of giant worms, and got a six-week penalty. Quickly, she tried to use the Time Scepter to get though her sentence quickly. However, this played into the hands of Savanti Romero, who caused the arrival of the scepter with black magic.
  • The Load: Due to not knowing how the Time Scepter works, and not really having any combat prowess, she's largely useless in a fight. Even the Turtles grow exasperated with her in her first appearance.
  • Time Police
  • True Blue Femininity: Her outfit is mostly blue and it matches her Innocent Blue Eyes.
  • Valley Girl: Her speech is this.

Miyamoto Usagi

Voiced by Jason Griffith

The guest-starring character from the comic Usagi Yojimbo.

  • Bash Brothers: With Leonardo. The two became very fast friends, and Usagi even goes to the point of calling Leo brother during "The Real World" parts one and two. It helps they have the same weapons and that Usagi's just a more cynical version of him.
  • Crossover: The characters and setting of Usagi Yojimbo show up more than once in the series, and "Across The Universe" features Raphael in one of Peter Laird's other stories, Planet Racers.
  • Early-Bird Cameo: He shows up in a flashback detailing how Drako tried to kill Splinter for defeating him, and helps Splinter.
  • Gratuitous Japanese:

    The Foot Clan 

The Foot Clan

An ancient order of shinobi, assassains and spies dating back to medieval Japan. In present day, they have semi-independent chapters all over the world, overseen by the japanese head council.

  • Avenging the Villain: The Foot are honor-bound to avenge the death of The Shredder, but agree to void the blood debt if the Turtles assist in bringing order to the New York branch.
  • Conservation of Ninjutsu: Ridiculously prone to this.
  • Cyber Ninja: The Foot Tech Ninja, which grants them invisibility.
  • Faceless Mooks: The rank and file ninja have virtually no defining characteristics.
  • Ninja: They're generally ninjas, trained by Shredder.

Oroku Saki/Ch'rell/The Shredder
See his real appearance 
Voiced by Scottie Ray

The leader of the Foot Clan, who works on various criminal operations. He's by and large the most personal nemesis of the heroes, and the most recurring one.

  • Adaptation Origin Connection: He's one of the main reasons the ship carrying him crashed on Earth, and thus ended up playing an indirect part in creating the Turtles and Splinter, his greatest enemies.
  • Adaptational Badass: He's capable of defeating the Turtles with ease, to the point they stay out of his league for a long while, in which he finally starts relying on augmented armors in fights, which help him against Splinter. He's also the one with the title that lives the longest.
  • Adaptational Villainy: While the Shredder is never a saint in any continuity, the Utrom Shredder is by far and away the most dangerous incarnation of the Shredder in the history of the entire franchise — after all, no Shredder can ever top nearly destroying all of reality itself.
  • Adaptation Species Change: The only incarnation of the Shredder, as far being the Shredder that the Turtles consider their Arch-Enemy, who was never human.
  • Arch-Enemy: He's the one that has most actively attempted to murder the Turtles, being part of the reason they came into existence to begin with. When he returns in Turtles Forever, his hatred for them has become so strong that he can't even stand the idea of different versions of the Turtles existing in other dimensions.
  • Bad Boss: His first on-screen action is murdering a Purple Dragon for failing him, and frequently maimed Baxter Stockman for his repeated failures until nothing is left of him but his brain and eye.
  • Big Bad: Specifically of Season 1, due to most of the criminal organizations in it being connected to him, but he still provides a lot of the action in Season 2 and 3.
  • Catch Phrase: "None of you will leave here/this place alive!"
  • Composite Character: The Shredder actually being the Utrom Ch'rell in some ways makes him this series' answer to Krang, as well as Oroku Saki. While Word of God says they tried to keep that similarity to a minimum throughout the show's run, Turtles Forever takes the idea and runs with it when they merge Dimension X technology with Utrom technology, giving him a Molecular amplification Exosuit that can grow to skyscraper size and transform into various weapons.
  • Dead Person Impersonation: Ch'rell has replaced the real Oroku Saki. Oroku Saki later turns out to be more alive than expected.
  • The Dreaded: Even after defeating him several times, just hearing that Ch'rell is involved in something is enough to make the turtles nervous about their chances of survival.
  • Establishing Character Moment: His first on-screen action in the series is to personally execute a Purple Dragon who failed him.
  • Even Evil Has Loved Ones: He seems to hold genuine concern for his adoptive daughter Karai. Until she refused to let him kill the Turtles.
  • Fatal Flaw: No matter which universe Shredder is from, the one constant is his massive ego.
  • Flunky Boss: This version almost always has some goons the Turtles have to fight through first before engaging him. In fact, almost every fight with him on his terms has him either using Foot ninjas to wear down the enemy before he arrives, or to distract them so he can launch surprise attacks.
  • Hijacked by Ganon: If there's a large-scale conflict in the series, he's most likely going to take center stage by the end of it, usually resulting in a Mêlée à Trois.
  • Human Popsicle: He was banished to the ice asteroid belt of Mor Gal Tal at the end of "Exodus Part 2" after being found guilty by the Utrom council. And he was found frozen in ice and freed by 1987 Shredder in Turtles Forever.
  • Hypocrite: In Turtles Forever, he complains about the 1987 Shredder using "[his] name" in vain, when Season 5 indicates that Ch'Rell used the name and title of the real Oroku Saki.
  • Know When to Fold 'Em: In "Exodus", after his spaceship is done being built, he plans on just leaving Earth to get his revenge on the Utroms, without even attempting to tie up his loose ends with the Turtles. He does, however, hint that he'll come back after his business with the Utroms are finished.
  • Multi Layer Facade: He's got a public identity which is Oroku Saki, the rich and well respected Japanese Businessman. Then he's the Shredder, a warlord who is using his public persona to gain power. And then his true identity originally only known by his adoptive daughter Karai is Ch'rell, an Utrom criminal who has been on Earth for over a millennium.
  • Omnicidal Maniac: Turtles Forever, where he's willing to destroy the entire multiverse, including himself, if it meant killing all existing ninja turtles. That includes his own daughter.
  • Pet the Dog: Downplayed. While he can throw it away at a moments notice, he seems to have some level of affection toward his higher level lieutenants; he personally raised Karai, trained Hun, rarely ever significantly punished them, and they're the only ones he listens to. He also respected the power of the Foot Mystics, which they reciprocated to some extent, even when they thought he was an "abomination".
  • Put on a Bus: He gets imprisoned on an asteroid in the endgame of Season 3, and doesn't show up again aside from cameos in Fast Forward and Back To The Sewers, until Turtles Forever.
  • Really 700 Years Old: Due to being an alien.
  • Revenge Before Reason: He comes to hate the Turtles so much that he rather destroy them and destroy the entire multiverse, including himself and his daughter Karai, than let them live.
  • Spikes of Villainy
  • Tin Tyrant: While a few other Shredder incarnations come close (such as in the movies and the Nick cartoon), the armor and attitude of that one fit the trope better.
  • Walking Spoiler: His real identity.
  • The Worf Effect: His Season One self is easily defeated in the Season Six episode "Timing is Everything", where he travels to 2105 and gets his ass kicked by Leonardo. It's implied that these events are part of a Stable Time Loop which caused the Shredder to become more ruthless in his hunt for the turtles Post-Season One — which would eventually lead to his final defeat. This is even indirectly referenced in Turtles Forever: not once in the movie does the Utrom Shredder directly fight with any of the turtles. He either points his army and elite henchmen at them or enlarges his suit Attack of the 50-Foot Whatever-style, giving himself an unfair advantage.

A high-ranking member of the Foot Clan

  • Ambiguously Evil
  • Anti-Villain: Rarely holds any enmity towards the turtles, fighting them on Shredder's orders.
  • Avenging the Villain: Her motivation for fighting the Turtles after they defeated Shredder.
  • Bad Boss: She treated the Foot Mystics more along the lines of weapons, and constantly ignored their opinions, saying that since she had the Heart of Tengu, they would do whatever they pleased. It didn't work that well in the long run.
  • The Bad Guy Wins: "Scion of the Shredder" has Karai seemingly killing Master Splinter and all but one of the Turtles (Leo), as well as destroying their lair. By the next episode it's revealed that they all survived, however.
  • Broken Bird: In seasons 4 and 5.
  • Co Dragon: After her introduction, she shares the role of The Dragon with Hun.
  • Contrasting Sequel Antagonist: In Season 4, after taking the role of The Shredder, she's much more active in hunting down and murdering the Turtles, to the point that she destroys their lair and most of their vehicles in the process, rather than being as passive as Ch'Rell. However, she lacks Ch'Rell's cunning and her hotheaded tactics cause the Foot Mystics to respect her less than her predecessor.
  • Corrupt Corporate Executive: Once she takes over her father's enterprise.
  • Daddy's Little Villain: She actually is the Shredder's foster daughter.
  • Dark Action Girl: Can usually take any one of the turtles head to head, though not all four like Shredder frequently can.
  • Demoted to Dragon: Originally in the comic, Karai was a Foot Clan commander on the same level as the Shredder, sent by their mutual commanders in Japan to clean up his messes.
  • The Dragon
  • Dragon Ascendant: In season 4. After Shredder's defeat she takes the mantle for her own.
    • She reassumes her role as co-dragon in Turtles Forever.
  • Enigmatic Minion
  • Evil Counterpart: To Leonardo.
  • Good Colors, Evil Colors: A very subtle one occurs with Karai in Season 4. Normally she wears pink lipstick, but for "Prodigal Son" she wears red lipstick, symbolizing her crossover into evil when she believed she's killed the Turtles. After Leo defeats her the next time we see her she's gone back to the pink lipstick, showing she's not so evil and such a threat anymore.
  • Heel–Face Turn: Though it doesn't happens until season 5.
    • Which extends to Heel–Face Revolving Door when she switches sides twice in Turtles Forever where the Shredder return now as an Omnicidal Maniac. This proves to be too much for her, and she sides with the turtles against him.
  • Holding Hands: Karai does this to Chaplin at the end of Season Five.
  • Honor Before Reason
  • Hooked Up Afterwards: Karai and Chaplin, after the season 5 finale hand-holding.
  • Lady of War
  • Leitmotif
  • My Master, Right or Wrong: This is the struggle that Karai faces in the second and third seasons whit her loyalty to her adoptive father, The Shredder, clashes with her more noble instincts. One of the forms this clash takes is in her reluctance to kill the turtles, who had agreed to help her restore the New York Foot in exchange for ending the syndicate's vendetta against the turtles. While the agreement was made under false pretenses—it was made under the assumption that the Shredder was dead and that Karai would be leading the Foot, which Karai knew was not the case—she still felt compelled to keep it, despite her father's wishes.
  • No, You: Karai's not very good at trash-talking. She does this several times to the Tengu Shredder.
  • Red Eyes, Take Warning
  • Shoulders of Doom: As Shredder.
  • Spikes of Doom: As Shredder.
  • Tin Tyrant: When she takes over the Shredder's mantle.
  • Took a Level in Jerkass: In Season Four, after the exile of Ch'rell. She gets better in Season Five and only antagonizes the Turtles again when the Utrom Shredder returns in Turtles Forever. After he goes absolutely insane and tries to destroy The Multiverse in his vendetta against all Teenage Mutant Ninja Turtles, she makes a permanent Heel–Face Turn and tries to stop him.
  • Tykebomb: An orphan found and adopted by the Shredder at an early age, he turned her into one of his most loyal and capable lieutenants. The Shredder, surprisingly enough, turns out to be a rather good parent (at least from her account) and the ensuing loyalty she feels to him is at the core of her character arc.
  • Undying Loyalty: This is what prevents her to make a Heel–Face Turn for most of the series; She genuinely respects the Turtles, almost has a friendship with Leonardo and knows to some extent that the Shredder's motives aren't exactly pure, but due to the role he played in her life, she feels like she owes him, and stays by his side no matter what. Even when he actually is defeated, she ends up blaming the turtles for it and going on a Roaring Rampage of Revenge against them. Eventually, it takes the Shredder trying to destroy The Multiverse (him and her included) to make her leave him once and for all.
  • Villain with Good Publicity
  • Wild Card
  • Worthy Opponent: To the Turtles in general, but typically to Leo.

Shredder Mutants

Hideously mutated clones of The Shredder, dressed in modified Shredder armor and trained to work as elite Foot soldiers.

Foot Elite

Elite ninjas of the Foot and the Shredders personal body guards and lieutenants.

  • Avenging the Villain: After the Shredders death at the hands of the Turtles, the remaining Elites swear a vendetta against both them, and the factions of the Foot now fighting for control over New York.
  • The Dreaded: Becomes this to Leonardo after the savage beatdown he recieves at their hands. They are not present in the comic book version of the storyline.
  • Elite Mook: They serve as the absolute best fighters of the Foot, second only to Shredder himself.
  • Enemy Civil War: They strike at all parties involved in the war over the New York underworld, including the Japanese Foot.
  • Flat Character: None of them really have any character traits beyond their blind loyalty to the Shredder. In the cartoon each Elite has a unique weapon, an axe, a spear, a poleaxe and a doublebladed sword, but thats about it.
  • Uncertain Doom: In the fifth season, they're taken down by the Tengu Shredder and are never seen again, not even during Fast Forward or Back To the Sewers. Whether they died or not is never adequately answered.

Dr. Chaplin

A young scientist who becomes the head of the Foot's science department in season 3.

  • Amazon Chaser: A look at his Amazon Blade Bots makes it clear that a large part of his crush on Karai rests on her ability to kick ass.
  • Improbable Age: Although the art style makes it somewhat hard to determine just how old he is, the various comments made about it suggest that he is either a teen or barely in his twenties when he debuts, which makes him a rather young for a doctor and way too young for a department head.
  • Mythology Gag: He looks like the 1987 human Baxter Stockman, sharing the same wardrobe, with the only difference being his hair color being red, but that's derived from Baxter's eventual mutation into a fly.
  • Punch Clock Villain


A highly skilled Foot Ninja who tries to bring the Clan back to its former glory in season 7, and who becomes Cyber Shredder's agent in the real world.

  • Animal Motif: The dragon—fitting, since he's also The Dragon
  • Convenient Replacement Character: Essentially only introduced in Back to the Sewers to replace Karai as the acting leader of the Foot, since it's heavily implied that she left with Chaplin after the season 5 finale
  • The Dragon
  • Evil Mentor: He is first seen running a martial arts school, whose students include Casey.
  • Flat Character: He doesn't serve much purpose besides being the Shredder's right-hand man.
  • Undying Loyalty: Even after the Foot essentially dissolved after Season 5, he still trained ninjas to prepare for the return of the Shredder.

     Purple Dragon 

Purple Dragons

A New York street gang consisting of mostly teenage thugs, thieves and killers.

  • Ascended Extra: Like the Shredder, the Purple Dragons were one-shot characters that appeared in the very first issue of the comic book, though unlike the Shredder, it would be decades before they became a permanent part of the Turtles rogue's gallery.
  • Starter Villain: The very first opponents the Turtles fought.


Real name: Hunter Mason. A hulking, tattooed gangster who serves as the leader of the Purple Dragons street gang.

  • Animorphism: To a mutant turtle, in Turtles Forever.
  • Arch-Enemy: To Casey in most continuities. He killed Casey's father.
  • Authority Equals Asskicking: One of the two constants about him is that he always is the leader of the Purple Dragons, and the strongest in the gang.
  • Badass Longcoat: At one point.
  • Badass Normal: A regular human with no mutation whatsoever, but still capable of giving a hard time to the Turtles of his own.
  • Berserk Button: Unless you want Hun to rudely tell you to leave him alone, do not persist with him that he placed an order. The result? Hun: (Growling) "GO AWAY! WE! PLACED! NO! ORDER!"
  • The Brute: He is not stupid, but still, he is the Shredder's biggest and strongest enforcer.
  • Canon Immigrant: He was originally created for the 4Kids show, but got popular enough to be adapted back into the comics, and later introduced (though considerably different) in the Nickeldeon cartoon.
  • Catchphrase: "Oh, crud"
  • Character Development: While initially very loyal to the Shredder, after learning about him being an alien, he leaves the Foot Clan and sheds a lot of his brute tendencies to turn the Purple Dragons from a petty gang of thugs into a lucrative crime organization, pulling off very successful heists in the process.
  • The Dragon: To Shredder, though he eventually becoming Co Dragon alongside Karai.
  • Dragon Ascendant: When Hun finds out Oroku Saki is actually an alien named Ch'rell he leaves The Foot Clan, and does a complete makeover of The Purple Dragons, transforming them from simple street thugs into a veritable army that pulls off some very high risk & high reward theft jobs from Multinational Corporations & even the military.
    • However come Turtles Forever after he gets mutated into Slash he willingly decides to get Demoted to Dragon & serve Ch'rell once again.
  • Empowered Badass Normal: In Turtles Forever.
  • Fingerless Gloves
  • Guilty Pleasures: In-show variation with Hun. Running the Purple Dragons is one thing, but who would've thought he plays the same MMORPG that Mikey does? Not to mention he, unknowingly, met the Turtles in it and helped them get Splinter's data bits.
  • Karmic Transformation: In Turtles Forever, he ends up mutated into a Slash-esque Turtle after being in contact with both 2003 Raph and the old cartoon's Mutagen. To say he doesn't take it well would be quite an understatement.
  • Large and in Charge
  • Leitmotif
  • Lightning Bruiser: Don't let his size fool you, Hun is astonishingly fast—more than fast enough to be a match for the turtles.
  • Most Gamers Are Male: Size doesn't seem to matter for him.
  • Punctuated! For! Emphasis!: Is it any surprise that Hun has at least one moment of this? Hun: "Arrrrrgh! Go away! WE! PLACED! NO! ORDER!"
  • Scars Are Forever: Hun sports a trio of matching scars on his face, courtesy of a pre-mutation Splinter.
  • Tattooed Crook: Hhe sports twin tattoos of the Foot and Purple Dragon symbols, removing the former after he leaves the organization for good.
  • Took a Level in Badass: In Season 4, Hun transforms the Purple Dragons from a petty street gang working for the Foot into a far more sophisticated organization operating on its own.
  • Would Hit a Girl: He was willing to hit April, hoping that losing her would cause the turtles to lose their fighting spirit. In City At War, Part 3, Hun smacks Karai around with a support beam.

     Superheroes and supervillains 

Baxter Stockman

An African-American Mad scientist and creator of the mouser robots.While he sold them off as a means to rid the city of the rat problem, he was really using them to rob banks while under the Utrom Shredder's employ.

  • An Arm and a Leg: ...and an eye, and another arm and another leg and so forth...until he's reduced to a literal Brain in a Jar .
  • Anti-Villain: Eventually.
  • Ascended Extra: He's a rather minor antagonist in most major TMNT incarnations, but ends up being one of the most recurring and plot-critical villains as the series goes on.
  • Back from the Dead
  • Bad Boss: He fully intended to murder April when she discovered the Mousers' true purpose. Sure, he's almost never in a position of authority again in the series, but this is pretty bad, and it is a small piece of a character so generally unlikeable that him being increasingly mutilated over the series' run (ironically as punishment for repeatedly failing the Shredder) elicits little in the way of sympathy.
  • Big Bad Wannabe: He really seems to want to be taken seriously as a criminal mastermind, but never manages to get very far in the process.
  • Black and Nerdy
  • Body Horror: In "Insane in the Membrane," after four seasons of losing body parts, Baxter Stockman finally obtains a new body via cloning. Soon enough, however, he discovers that it's unstable, as his limbs start deteriorating and melting off. His mind had gone with it before being retrieved and placed back in his jar.
  • Brain in a Jar
  • Break the Haughty: Pretty much his entire career is this, but "Insane In The Membrane" is where it really sinks in.
  • Chronic Backstabbing Disorder: He frequently attempted to sabotage the people working with him, generally to make himself look better, or because he wanted revenge. He cuts it out after being hired by Agent Bishop, for the most part.
  • Clone Degeneration
  • Corrupt Corporate Executive: He was one before his body kept getting destroyed.
  • Determinator: He never seems to lose his smug edge or ability to concoct new schemes, no matter how many limbs get cut off. The Black Knight would be impressed.
  • Evil Is Hammy
  • Evil Mentor: For April.
  • Fingore: Occurs to him in "Insane in the Membrane."
  • Four Eyes, Zero Soul: In most continuities, he wears glasses.
  • Hoist by His Own Petard: In "Return to New York".
  • Hypocrite: He calls mutants like the turtles "stupid freaks." This coming from a talking head in a robot body. This version is notoriously vain, so it fits him perfectly.
  • I Just Want to Be Normal
  • Implacable Man: Lampshaded by Leonardo and Shredder:
    Leonardo: What do we have to do, to stop this guy?
    Shredder: I have asked myself that question many times.
  • Irony: Interestingly, in the original TV Show, he ended up getting a Fate Worse Than Death, in a Lighter and Softer show, while in this darker show, not really mattering since Fast Forward still had Dark elements, Baxter gets a somewhat happier ending
  • Leitmotif
  • Mad Scientist
  • Omnidisciplinary Scientist: His primary field is usually robotics, evidenced by his famous Mousers, but he'll show expertise in everything from genetics to archaeology as suits the plot.
  • Powered Armor: Occasionally wear these.
  • Serial Prostheses: Thanks to the Shredder's attitude towards failure. He loses an eye, a hand, and ends up in a wheelchair before trying to take his revenge in a Mini-Mecha. When that fails, he's reduced to a head attached to a robot. It gets worse from there.
  • Scars Are Forever
  • The Starscream: To the Shredder.
  • Spared by the Adaptation: Downplayed horribly. He doesn't die... But he really wishes he had.
  • Third-Person Person: He is prone to this when gloating.
  • Used to Be a Sweet Kid: He used to be a fairly benevolent and principled scientist too until his ego and arrogance got the better of him.
  • Was Once a Man: He never stays human.
  • We Can Rebuild Him
  • Wetware CPU: As loses more and more of his body, Baxter begins becoming this.
  • Yank the Dog's Chain: "Insane in the Membrane" for him.

The Slayer / The Rat King

A man dressed up in rags and bandages who shares a rapport with rats.

  • Aborted Arc: His episode ending, which clearly indicated he was going to return, but it never happened. Closest he ever came to returning was watching April and Casey's wedding in the final episode.
  • Adaptational Early Appearance: Inverted. His first appearance, "Bishop's Gambit", doesn't occur until Season 3, late in the series, and doesn't don the Rat King identity until "I, Monster", a Season 4 episode. Due to this, he doesn't play any role in the City At War arc.
  • Ax-Crazy
  • Beast Man
  • Canon Character All Along: The Slayer that he originally was appears to just be another one of Bishop's one-off experiments, but ends up becoming The Rat King.
  • Comic-Book Movies Don't Use Codenames: He is never referred as "Rat King".
  • Healing Factor: As The Slayer.
  • Invisibility: As The Slayer.
  • Mind Control: Subverted. It is never said how he controls rats, but presumably it is related to his being formed from mutated rat (Splinter's) DNA.
  • Mix-and-Match Man: He is one of these, using DNA from Bishop, Splinter, among other possible sources.
  • Spared by the Adaptation: He was Killed Off for Real in the Mirage Comics, which the show is more closely based on, but lives in this version.
  • Super Soldier: His Slayer persona was designed to be one. He is a prototype bio-mechanical super soldier created by Agent Bishop using genetically manipulated, alien, the turtles, his own and Splinter's DNA.

Silver Sentry

One of Michelangelo's superhero idols and the leader of the modern-day Justice Force.


A hydrokinetic super-hero from Japan who joins the Justice Force in season 3.


An psychokinetic super-hero from India who joins the Justice Force in season 3.


A sentient nanomachine colony who escapes its creators and causes trouble.

Green Mantle

Green Lantern if Green Lantern got his powers from a cape.

Turtle Titan II

A man who takes on Michelangelo's old super-heroic identity.

Dr. Malignus

Silver Sentry's arch-enemy, who uses his engineering prowess to commit super-crime.

  • Dr. Genericius
  • Hypno Trinkets: The mind-control bugs he uses in his debut activity.
  • Mad Scientist
  • Morally Ambiguous Doctorate
  • The Bus Came Back: He made just one appearance in the first season during Michelangelo's teamup episode with Silver Sentry and remains absent for the remainder of the series(aside from appearing in a story told by Michelangelo during Fast Forward) until the seventh and final season where he makes one more official appearance.

    The Battle Nexus 

The Ultimate Ninja

A warrior who comes to Earth to challenge Leo to mortal combat.

The Daimyo

Ruler of the Battle Nexus and The Ultimate Ninja's father.


A Battle Nexus Championship contestant who was defeated by Splinter years ago.


A Battle Nexus Championship contestant with an animus towards Michelangelo.
  • Ambiguously Evil: While he eventually tries to kill Michelangelo for purely selfish reasons, he also formed part of Traximus' rebel army, which makes it rather hard to get a sense of him.
  • Sdrawkcab Name: The character is meant to be a homage to The Hulk.
  • Sore Loser: Although he has a point about only losing on a technicality, it eventually becomes clear that he doesn't really give a damn about the Battle Nexus Championship or its rules.
  • Super Mode: Inverted, more or less, as he spends way more time in his hulked-out form than he does in his smaller state.

    The Ninja Tribunal Arc 

The Ancient One

Hamato Yoshi's adoptive parent and, for a time, Leonardo's sensei.
  • Acrofatic
  • Back for the Finale: He's one of the guests at Casey and April's wedding and takes part in the ensuing battle against the Cyber Shredder.
  • Big Good: Shares the role with Splinter in the fifth season after the apparent deaths of the Tribunal.
  • Gass Hole: Early on, he teaches Leo a lesson on how he can't win all his battles by getting him pit against some near invincible warriors. How did the Ancient One put through Leonardo through this lesson? By farting and alerting said warriors to their presence.
  • My Greatest Failure: He blames himself for not doing anything about the darkness in Mashimi's heart before his murder of Tang Shen.
  • No Name Given
  • Obfuscating Stupidity: Once Leonardo learns of his true nature, he drops the crazy mentor facade, though he remains fairly whimsical until the fifth season.
  • Old Master
  • Reasonable Authority Figure: Leonardo and Michelangelo even wish they could be studying under him over the rough Tribunal.
  • Trickster Mentor: At first.

The Ninja Tribunal

A quartet of long-lived ninja masters who have made it their lives mission to stop the Demon Shredder. Their names are Kon, Juto, Chikara, and Hisomi.

The Acolytes

Four martial artists who were kidnapped along with the turtles to serve as the Ninja Tribunal's apprentices. Their names are Faraji Ngala, Joi Reynard, Adam McKay, and Tora Yoshida

The Tengu Shredder/Oroku Saki

Voiced by: Scottie Ray

The original Shredder, namesake of Ch'Rell's identity, and the antagonist of Season 5.

  • Berserk Button: Doesn't take kindly to the Mystics suggesting he should kill Karai, stating he does whatever he pleases.
  • Big Bad: For Season 5.
  • Contrasting Sequel Antagonist: He's much less subtle and more active in his pursuits to kill his opposition, and doesn't have a goal involving getting back to his home planet or getting revenge; he just wants to Take Over the World. He also lacks the personal enmity the previous Shredders had with the Turtles, and thus frequently underestimates them.
  • Deal with the Devil: In exchange for sparing the Tengu's life, Saki merge with him and gain unspeakable power.
  • Divergent Character Evolution: When he cameod in Back To The Sewers, he looked much more top-heavy and the cover for his arms looked more like black bandages, along with having a much "pointier" aesthetic, presumably to further distinguish himself from Ch'Rell's overall look.
  • For the Evulz: Most of his actions are caused by a love of spreading fear and destruction.
  • Fusion Dance: Both Saki and the Tengu merge together.
  • Greater Scope Villain: The inspiration for Ch'Rell's identity and the true master of the Foot Mystics, whose goal is to resurrect him. He doesn't come into action until the second half in Season 5.
  • Hijacked by Ganon: Downplayed; while he's not the same as Ch'Rell, the conflict of Season 5 is against the one with the original Shredder title.
  • Loves the Sound of Screaming: Admits he can't wait to hear the screams when he remakes the world in his image.
  • One-Winged Angel: He can transform into large dragon when more strength is needed.

The Shredder's Heralds / Foot Mystics

The Demon's Shredders, who had been forced to serve the Utrom Shredder until they engineered their freedom.

  • Ascended Extra: They were one-off villains for the penultimate arc of the first season, and voiceless. They return early in the fourth season, and nearly mentally break the Turtles, discover the location of their lair, and facilitate a plot that leads to the return of the Tengu Shredder, becoming the Big Bads for the first half of the fifth season before returning to their role as his Dragons.
  • Big Bad: For the first half of the fifth season.
  • Because You Were Nice to Me: A non-romantic example; though they deem Ch'Rell an "Utrom abomination", they appreciated his large amount of respect for their powers when they served him, in comparison to his daughter, who cares less what they think.
  • Elemental Powers
  • The Dragons: For the demon Shredder
  • Giant Space Flea from Nowhere: Their first appearance is almost abrupt, with the Turtles suddenly finding themselves fighting against explicitly supernatural enemies. Lessens later on as we learn the Utrom Shredder acquired their seal at some point.
  • Revenge Before Reason: Despite their loyalty to the demon Shredder, they are obsessed with getting revenge on Karai. They question him why he isn't concern to punish Karai for using his name, he tells them he's cares more about ruling the world. Though they don't wish to deter their master with his plans, this does not sit well with them. They also fume over the Shredder's lack of action when the Turtles and their allies attack their fortress.
  • Undying Loyalty: To the Demon Shredder.
  • Voluntary Shapeshifting
  • You Have Outlived Your Usefulness: Demon Shredder let them get killed.

    Fast Foward 

Cody Jones

Casey and April's great-grandson and heir to both O'Neil Tech and the Jones fortune.


Cody's robotic caretaker, who only barely tolerates the turtles.

Darius Dun

Cody's uncle and legal guardian, he uses his position as the C.E.O. of O'Neil Tech to facilitate various shady dealings.


An alien invader who has determined that Earth is the ideal planet for him to spread his gene-seed.
  • Arc Villain: Of Fast Forward.
  • Back for the Finale: After his own Time Window goes haywire, he disappears until the penultimate (though for all effects the final) episode of Fast Forward.
  • Big Bad Ensemble: With Darius Dun.
    • Big Bad Duumvirate: He later forms one with Darius Dun for the first half of Fast Forward.
  • Expy: He shares more than a few similarities to Lord Dregg.
  • Karma Houdini: He tricked Torbin Zixx into smuggling a bomb onto a spacecraft and while Zixx did rat him out to the turtles, who in turn reported it to Bishop, Sh'Okanabo never got in trouble for almost hurting many innocent beings.
  • Knight of Cerebus: Episodes that feature him as the main antagonist are far more serious with larger ramifications.
  • Killed Off for Real
  • Light is Good/Dark is Evil: He looks dark and works in the shadows, is never seen walking around in daylight, if weak enough, sunlight can hurt him and he was killed by a solar grenade.
  • Spikes of Villainy
  • The Virus: Anyone infected with his gene seeds becomes a Kanabo drone subservient to him.
  • Voluntary Shapeshifting

Constable Aloysius Biggles

A robot who serves as an officer of the New New York Peacekeepers and who keeps running into the turtles.
  • British Copper: In intent if not in reality.
  • Butt Monkey: To the point that the main gag of a preview of an episode revolved around his really long fall from a skyscraper, and Michelangelo finally admits at the end of the promo that someone should probably save him. Funnily enough, in the episode proper this is not played for laughs.
  • Catchphrase: “'Allo 'Allo 'Allo. Wot's all this then?”
  • Inspector Javert: Occasionally, most notably in “Playtime's Over”
  • Ridiculously Human Robot: Despite being presumably programmed for the job, he rather dislikes the paperwork it involves.


An A.I. who serves under Sh'Okanabo.

Starlee Hambrath

An O'Neil Tech intern and friend of Cody Jones.


A cyborg who runs the Street Phantoms, a New York gang.

The Inuwashi Gunjin

A quartet of winged humanoids who serve as Darius Dun's reluctant enforcers.

  • Anti-Villains: They work for Darius Dun only because they have been implanted with electronic machines that Dun uses to torture and contain them. They kidnap Cody and threaten to kill him if Dun (who needs Cody alive) won't free them. They note the turtles' honor for repeatedly saving Cody who's little help to them (at the time). They finally decide to follow the turtles' example of honorability and give them time to escape from drowning.
  • Forced into Evil
  • Heel–Face Turn: They all pull one once they are finally freed from Dun's control.
  • Last of Their Kind
  • Proud Warrior Race Guys: Their race was once the most feared force of earth and sky.
  • Winged Humanoids
  • Worthy Opponents: As they witness the turtles saving multiple times Cody who's not much of a help in a fight, they remark that to be truly honorable.

The Dark Turtles

Created by Sh'Okanabo from the turtles' genetic material, these four mutant turtles serve Darius Dun. They are all voiced by the same actors for the original turtles.

  • Big Brother Instinct: Kind of a grey area. Towards the end of "DNA Is Thicker Than Blood", Dark Leo divides up the meat among his brothers. This action is so unexpected that it sparks confusion among them.
  • Color-Coded Characters: The color of each turtles' skin more or less corresponds to their counterparts' bandanna colors.
  • Dark is Evil: At first. They were more than eager to try destroying their original counterparts.
    • Dark is Not Evil: They have the capacity to be better if they were given the chance.
  • Dumb Muscle: Dark Raph. He was so stupid that he couldn't pick up Mikey's sarcasm.
  • Evil Twins
  • Forced into Evil: While it doesn't occur in the same way as with their predecessors the Gunjin, the episode “D.N.A. is Thicker Than Water” implies that they have the capacity to be better turtles if it weren't for the fact that they are forced to work for Dun.
  • Geek Physiques: Dark Don is the tallest and skinniest of the quartet.
  • I'm a Humanitarian:
    Dark Raph: Let's crack your shell open and see if there's a yummy cream filling inside!
  • Laughing Mad: All of them, primarily Dark Mikey.
  • Oddball Doppelgangers
  • Off with His Head!: In their first 2 appearances, Dark Leo threatened to cut off someone's head.
    Dark Leo: *holding his sword next to Cody's neck* No sudden moves, or your friend here loses his head.

    Leonardo: How long have you been working for Dun?
    Dark Leo: Details, details, you should be paying attention to more immediate matters, like keeping your head on!
  • Psycho Rangers
  • Reptiles Are Abhorrent
  • Slasher Smile / Psychotic Smirk: They at least show off one.

Torbin Zixx

A famed mercenary who has several run-ins with the turtles.
  • Advertised Extra: He appears in the opening titles, despite his sporadic appearances in the series.
  • Combat Pragmatist
  • Con Man
  • Even Evil Has Standards: Deliver/smuggle an illegal package for an alien? Sure. Said package turns out to be a bomb that could've potentially hurt many innocent humans and aliens? Yeah, big mistake.
  • Heroic Sacrifice: Volunteers to make one in the final episode of Fast Forward to save Earth from a dark matter asteroid. It's actually his ship, which he escaped to with a device that had been jury-rigged to destroy the asteroid.
  • Wild Card / Chaotic Neutral

Triple Threat

A pro-wrestler turned criminal who sports three heads, each with its own personality.


A government agent who will do absolutely anything to protect Earth from aliens invasion. Head of the Earth Protection Force.

  • 0% Approval Rating: In modern times, the Turtles, Splinter, Leatherhead, and even the Foot Clan thoroughly despise him and Raphael even went on record as to say he hated Bishop more than his Arch-Enemy Hun. Even an important political ally to Bishop like the President of the United States itself doesn't seem to like Bishop all that much and has chewed Bishop out for constantly acting on his own. And even Baxter Stockman, the closest thing Bishop has to a friend in the show, quickly grew disillusioned with working under Bishop, based on how Bishop has constantly stalled him from working on a new human body or brought him back from the dead even though Stockman wanted more than anything to rest in peace.
  • Alien Blood: Despite being human.
  • Ambiguously Human: He was definitely human at some point, but after a certain event some 200 years ago, it's no longer clear what he is.
  • Anti-Villain: He genuinely tries to protect humanity from potential alien invaders. The problem is, he is sadistic, amoral, suffers a huge case of Fantastic Racism against aliens and mutants as a whole, and conducts horrible experiments o reach his goals.
  • The Atoner: In Fast Forward.
  • Badass Longcoat: Part of his signature look.
  • Back for the Finale: After being absent for the entirety of the final season, he makes a cameo watching April and Casey's wedding with approval.
  • Benevolent Boss: He can be stern or angry toward Stockman, but for the most part, he shows genuine concern for his condition (if just because he still needs Baxter's knowledge) and, unlike the Shredder, never threaten to kill or mutilate him for his failure.
  • Big Bad Ensemble: He's the most prominent antagonist in the third season not aligned with the Foot. After the final defeat of Ch'Rell, in the fourth season, he forms an ensemble with Hun and Karai, with Stockman as his Dragon.
  • Canon Immigrant: A character who talks while off-panel in one issue of the Mirage Comics has been confirmed by Word of God to be him.
  • Clone Degeneration: He survived so long by regularly cloning himself in a new body that ends up degenerating after a while, forcing him to do it over and over again.
  • Combat Pragmatist: He ends up using his own tie to fight the Turtles, Karai and Hun and still continues to kick ass.
  • Dark is Evil: As a villain, his suit is black.
  • Enemy Mine: Twice:
    • When the mutagen he used to create a fake alien invasion ends up unleashing mutants on New York, he teams up with the Turtles and Leatherhead to end it.
    • In the fifth season, he is amongst the many villains who join force with the Turtles to stop Tengu Shredder.
  • The Extremist Was Right: In "Aliens Among Us".
  • Four Eyes, Zero Soul: He's never seen without a pair of sunglasses, and he's a bad guy.
  • Freudian Excuse: In the 1800s, Bishop was a soldier in the Civil War who was abducted by aliens, being experimented on and genetically altered, turning him into the xenophobic Well-Intentioned Extremist he is in modern times who's willing to cross any moral boundary in order to keep Earth safe from alien incursions. Given his past, it's quite understandable why he became the man he is today, though in no way does this justify all the lives he's ruined and the people he's hurt. His actions become even less justified when you consider that some of the beings he's either tortured or tried to torture such as Leatherhead, the Turtles, and Splinter are actually native to earth and are notably NOT aliens in any sense.
  • Heel–Face Turn: In Fast Forward.
  • Heel Realization: In Fast Forward, he became a better person after an alien he was experimenting on saved his life, altering his view of extraterrestrials considerably.
  • He Who Fights Monsters: He was experimented on and never wants that fate to befall another human, but himself has experimented on aliens, regardless of their innocence.
  • Hypocrite: He wants for no other human to befall the fate of being experimented on by extraterrestrial forces, but has done the same to aliens themselves. This isn't even getting into the fact he's heavily implied to have mutated Finn in "Dragon's Brew", whose wedding he was the best man for.
  • Iconic Sequel Character: He's one of the most well-known characters in the 2003 incarnation, despite his first appearance being in Season 3, a rather late stage of the series.
  • Karma Houdini: Though he at least learnt from his mistakes and tries to atone for what he did.
  • Light is Good: In Fast Forward where he's become good, his suit is white.
  • One-Man Army: He can hold his own against all four of the turtles, AND Karai and Hun all at the same time. He's also seen effortlessly fending off the Foot Elite in Exodus.
  • Promotion to Opening Titles: From the fourth season to the sixth season.
  • Supporting Leader: When the Turtles and Karai are fighting the Demon Shredder, Bishop takes command of the Purple Dragons AND the Justice Force along with his own men.
  • Unwitting Pawn: In "Good Genes", he is promised an alien artifact of great power by an unknown entity, and has the Turtles retrieve it for him. When he gets it, he ends up destroying it, which frees the Foot Mystics from Karai's control, leading to the return of the Demon Shredder.
  • Villain with Good Publicity: A downplayed example. He's a very secretive government agent and very few people know of his actual existence. However, he has the backing of the United States government and by the fourth season, the unconditional support of the President himself, which makes him arguably as big of a threat to the Turtles as the Foot Clan, if not moreso. He becomes yet another downplayed example by the time of Fast Forward because by that time, everyone knows of his existence and he's extremely well liked by almost everybody on Earth... but by that time, he's pulled a Heel–Face Turn and is no longer an actual villain.
  • Well-Intentioned Extremist: In the present.

Yukio Mashimi

Hamato Yoshi's friend and surrogate brother.

  • Expy: For Oroku Nagi, who was Adapted Out, being the one to compete with Hamato Yoshi for Tang Shen's feelings.
  • Green-Eyed Monster: Eventually, Tang Shen not requiting his feelings and Hamato Yoshi going onto a promising ordeal resulted in Mashimi murdering Tang Shen, and betraying Yoshi to the Foot Clan.
  • My God, What Have I Done?: Before he dies, he asks Yoshi to forgive him for all the horrible atrocities he caused.
  • Small Role, Big Impact: Without him betraying the Utroms and Yoshi to the Foot Clan and his murder of Tang Shen, Splinter and the Turtles as they are may well not have existed.