Characters from the long-running comic book series Teenage Mutant Ninja Turtles, as well as some exclusive to some of its non-comic incarnations. Note: Several characters' allegiances shift between incarnations. They have been placed in the side they are most usually associated with.
Heroes
Leonardo
Leads. Always in control. Identifiable by his blue bandana and his twin swords.
Appears in: all continuities.
Authority Equals Asskicking: Consistently the most skilled Turtle, he falls into the leadership role by default.
Child Soldiers: Of the four, it's Leonardo who exemplifies this the most.
Combat Pragmatist: Leonardo's sense of honor dictates that he fight fairly, but when he's pushed into a corner or there is no other alternative, he will not hesitate to slice off your head.
Nerves of Steel: Captured by aliens, trapped thousands of miles from Earth with no way back, poisoned and weaponless? For Leonardo, that's a training run.
A Protagonist Shall Lead Them: Leonardo usually gets the most lines of dialogue, and most of the stories are told from his perspective. Even when he's not presented as the main character (such as the TMNT movie), he plays a major role.
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.
Sliding Scale of Idealism Versus Cynicism: In the 4Kids series, he starts out at the very end of the Idealism scale, even believing the best of the Shredder and then this 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: All the turtles train hard, but Leonardo—whether or not by his own design—is almost always subjected to the kind that involves complete isolation, distant countries, and/or imminent death.
In the 4Kids series, Leonardo as a child is suffering from 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 all incarnations, the turtles all go through this, but Leonardo is the one who most clearly demonstrates the trope. One example is in the first season of the 4Kids cartoon where 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.
Well Done Son Guy: Most of what Leonardo does is to please Splinter. Whether or not this is a good thing is still a debate in fandom.
What the Hell, Hero?: Leo gets this in the 4Kids cartoon from his brothers and Splinter when he's on the verge of becoming a Knight Templar.
Wise Beyond Their Years: In childhood flashbacks, he's usually the turtle acting like the adult. And for a teenager, he deals very well with duties and responsibilities most adults would be unable to fathom.
Raphael
Is cool but crude. Throws the first punch. He wears red and fights with a pair of sais.
Appears in: all continuities.
Aloof Big Brother: Partially inverted. He's younger than Leonardo and Donatello making him an aloof little brother, but older than Michelangelo, playing straight for him.
The Berserker: Mostly (every continuity but Fred Wolf cartoon).
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.
Also an example of It's a Wonderful Plot, where a character often sees that their team or the whole world is worse off for their absence.
Brainwashed and Crazy: Not quite brainwashed, but mutated and certainly crazy enough to live up to the spirit of the trope during the Good Genes arc— unwitting Face Heel Turn included.
Crazy-Prepared: "What I really want to know is why Don carries around a pigeon puppet..."
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 in the 2003 series.
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.
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.
Layman's Terms: Often the one doing the translating, sometimes visibly annoyed.
OoC 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.
Weirdness Magnet: Even amongst his brothers. He's been to at least three different worlds/dimensions that the others haven't, at any rate.
Michelangelo
Is a party dude. Wiseguy. The most laid-back of the turtles, who lists among his interests pizza, comic books, and more pizza. Wears an orange-yellow bandana, and duels with nunchaku.
Ascended Fanboy: Sorta, he's a big comic book geek who happens to be a superhero himself.
In the Mirage comics he's a comic book geek who gets to write for comic books and even becomes a published novelist.
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. Yup.
Taken to it's furthest extreme in 2007's TMNT where Mikey is the shortest turtle and has huge adorable Blue Eyes (we know it doesn't make sense, but it's cute, dammit)
Big Eater: In the 'Fred Wolf cartoon, 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.
Butt Monkey: Especially in the cartoons. If any of the Turtles klutzes out or has something bad happen to them for comic effect, it's Michelangelo.
Characterization Marches On: Depending on the version, really - in the comic books, he isn't really a party dude, but more of a down-to-Earth type of guy as opposed to his brothers. He was able to author a book at one point.
In the Mirage comics he often traded back and forth with Donatello as The Smart Guy with Donny being the expert in science and technology while Mikey's specialty was culture and literature.
Crouching Moron, Hidden Badass: (4Kids series): Although he can always kick ass, his skills will occasionally take a bump as the plot requires, allowing him to take on foes that would normally defeat him or his brothers.
Hard Work Hardly Works: Although the trope is disproved by Leonardo, there is an element of this to Mikey's abilities, and he is consistently considered to be the most naturally gifted of the turtles despite his lack of focus and dedication to training.
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.
Lightning Bruiser: Michelangelo runs faster than Leo and Don and has more health than all of his brothers. However, his nunchucks are slow and have little range (Turtles in Time, The Arcade game, Manhattan Project).
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.
The Red Mage: In the games, average movement speed and faster attack speed than Don, but defensively weaker than Leo.
Surfer Dude: Mostly in the 'Fred Wolf cartoon, although aspects of this remain in other incarnations.
Took a Level in Jerkass: In the Next Mutation series. To a lesser extent, in the 4Kids series as well.
Trademark Favorite Food: Though pizza is the favorite food of all four turtles, Michelangelo eats it more obsessively than the other three, especially in the 'Fred Wolf cartoon.
Check it out, another one found! The female Ninja Turtle, from the Next Mutation series. Wears a light blue mask (with braided tails) and fights with iron fans and mystical orbs. Don't ask Peter Laird about her.
Cursed with Awesome: April is turned into a fish mutant in one episode of the Fred Wolf cartoon. She's understandably upset about it, but it saves her life when the villain's base is flooded and she's able to breathe underwater like the Turtles.
Motherly Scientist: In the IDW Comics, where she becomes quite attached to the pre-mutation turtles and even gives them their names.
Odd Friendship: In most adaptations Splinter and April strike up a deep but rather strange friendship. April is sometimes perplexed by the various personality quirks of each turtle while Splinter is exasperated having seen this all before.
Race Lift (Mirage comics): Although her race was never established within the comics, or even agreed upon by the creators, Kevin Eastman used to draw her with distinctively non-caucasian features, which went away when he stopped drawing.
An eccentric vigilante who fights crime with various sporting tools (baseball bats, hockey sticks, etc.) Tends to have the most in common with Raphael.
A mutant alligator/crocodile (depending on the incarnation) who fights, then befriends the turtles. Generally the subject of a lot of abuse.
Appears in: Mirage comics, Archie Comics,'Fred Wolf cartoon, 4Kids cartoon.
Adaptational Villainy: His original cartoon incarnation was made a villain, and he starts out that way in the Archie comic until he becomes a Mutanimal.
Metamorphosis: From human to humanoid alligator in the Archie comic book, from alligator to humanoid alligator everywhere else.
You Can't Go Home Again: In the Mirage and 4Kids cartoon continuities, Leatherhead initially yearns to rejoin the Utroms.
Professor Honeycutt/The Fugitoid
A scientist whose mind was accidentally transferred into a robot's body. Forced on the run by groups seeking to obtain his plans for a teleporter, he eventually meets and befriends the turtles.
Cursed with Awesome: In his debut appearance, he gains a Hulk-like mutation power that sporadically causes him to turn into a huge, muscular yellow-skinned mutant with a metal arm and spikes.
Magic Pants: Averted the first time he transforms, but played straight on all subsequent occasions.
The Pirates Who Don't Do Anything: We never actually see Carter at college. Either his attendance rates are lousy, or his college has one heck of a long summer break.
Put on a Bus: Halfway through the final season, he's taken away to the future to get his mutation cured. We never see or hear from him again, so whether or not the cure was successful, we'll never know.
Renet
An apprentice "Timestress" whose job it is to oversee and protect the timestream.
Appears in: Mirage comics, 4Kids cartoon
Character Development: (Mirage) Initially a ditzy, irresponsible and overly impulsive girl, she eventually evolves into a mature, responsible and self-reliant woman — after having spent some time as grim-faced, solemn and reluctant. What makes it confusing is that, thanks to her traveling back and forth through time, we don't necessarily see this development in chronological order.
In fact, we're informed that her parents originally made her take the job as an apprentice timestress in the hope that she would undergo some much-needed Character Development.
Deus ex Machina: In the Mirage comic Juliet's Revenge the fully-adult, post-Character Development Renet plays this role (having changed so much that the Turtles don't recognize her at first). For the most part, however, she averts this.
Forgotten Phlebotinum: She's completely and inexplicably absent from the Fast Forward season of the 4Kids cartoon, where the Turtles are stuck in the future — because if she'd appeared she could instantly have fixed their predicament.
Ms. Fanservice: (Mirage) About the only thing that stays consistent about her appearance is her huge breasts and tendency to wear skintight (and sometimes rather revealing) clothes.
Most Common Superpower: It's especially prominent in the Mirage comic (especially if Jim Lawson is drawing her), but the 4Kids cartoon version is notably endowed as well.
Shout Out: The third movie prominently features a time travel scepter that looks very similar to Renet's.
Took a Level in Badass: (Mirage) It's a long way from the Distressed Damsel we're first introduced to, to the nearly god-like woman who shows up to save the Turtles from certain death.
Villains
Oroku Saki/The Shredder
A Ninja Master with ties to the New York underworld, and the franchise's most visible villain.
Note: While all Oroku Sakis are Shredders, not all Shredders are Oroku Sakis.
The Utrom Shredder was one in an alternate Bad Future. Even before that there was an episode in the 1987 cartoon with the same premise of Shredder being ruler of the world in a Bad Future, however, due to the decay he suffered in that version, he was more inept than evil on that occasion and even wanted to go to a world where he wasn't ruler.
One-Winged Angel: Super Shredder in the movies and video games during the Fred Wolf cartoon era. Utrom Shredder simply has enlarged exo-suits, Demon Shredder can turn into a dragon.
Hot Amazon (4Kids cartoon): When Dr. Chaplin bases his Amazon Blade Bots on her, it's kinda clear that her ability to kick ass is a large part of her appeal.
Mad scientist and creator of the mouser robots. Never quite seems to remain whole (or even human, in some versions).
Appears in: Mirage comics, 'Fred Wolf cartoon, Archie comics, 4Kids cartoon, Dreamwave comics, IDW Comics.
Animorphism: His Fred Wolf 'toon incarnation eventually gets turned into a fly.
Anti-Villain: Eventually, in the 4Kids cartoon. He started out as one in the Fred Wolf cartoon but went crazy when he became a fly.
Attention Deficit... Ooh, Shiny!: In the Fred Wolf cartoon, in his later episodes he would sometimes suffer from this due to having the mind and attention span of a fly.
Body Horror: In 4Kids' "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. Worse still, his mind is going with it...
Butt Monkey: In both the the Fred Wolf cartoon and 4Kids cartoon incarnation.
Horrible Judge of Character: In the Fred Wolf cartoon, he agrees to help Shredder even though he approaches him on the streets in his full villainous garb and it gets worse from there. Even when Baxter turns into a fly as a result of Shredder sending him to Dimension X, as all it takes for Baxter to change from wanting revenge on Shredder to wanting revenge on the turtles is Shredder telling him that it was the turtles' fault.
Irony: Interestingly, in the original TV Show, he ended up getting a Fate Worse than Death, in a Lighter and Softer show, while in the darker show, not really mattering since Fast Forward still had Dark elements, Baxter gets a somewhat happier ending.
Used to Be a Sweet Kid: In the 4Kids series. He used to be a fairly benevolent and principled scientist too until his ego and arrogance got the better of him.
Lightning Bruiser: Don't let his size fool you, Hun is astonishingly fast—more than fast enough to be a match for the turtles.
Tattooed Crook: In the cartoon, he sports twin tattoos of the Foot and Purple Dragon symbols, removing the former after he leaves the organization for good. In the comic books, he sports a dragon tattoo on his right arm and hand, an one of a human vertebra over his left arm and back.
Bishop
A government agent who will do absolutely anything to protect Earth from aliens invasion. Head of the Earth Protection Force.
An alien general fighting a losing war, and who turns to Earth for assistance. A small, brain-like creature, he often uses a robotic exoskeleton to move around.
Appears in: 'Fred Wolf cartoon, Archie comics, IDW Comics.
Human gang members who were mutated into a warthog and rhino respectively, and serve as henchmen to the Shredder. Neither of them are particularly bright. Seen in their human forms in the IDW comics.
Appear in: Fred wolf cartoon, Archie comics, IDW Comics.
Becoming the Mask: In the Archie comics series, the animal part of their natures began taking over more and more. This actually increased their intelligence, while also making them more neutral and less evil.
Character Development: The Archie comics series gradually increased their intelligence and made them less evil as their animal natures took over more and more.
Friendly Enemy: In their final appearance in the Archie comics series, they hijack the spaceship used by Krang and his henchmen to reach Earth, using their guns to "convince" the Turtles not to stop them. However, Bebop and Rocksteady cheerfully accept Leonardo's request to take Krang and his goons back to the prison planet they escaped from, before returning to the Eden-like planet they've made their new home.
The Millstone: On many occasions Shredder may well have won if not for their bumbling. Of course then there would be no more show. They even end up costing Utrom Shredder an otherwise clear-cut victory in Turtles Forever.
Team Rocket Wins: Their final appearance in the Archie comics series has them convincing the Turtles not to fight simply by pointing their guns at them.
A man dressed up in rags and bandages who shares a rapport with rats. Varies wildly within incarnations—descriptions for each can be seen in the other Wiki.
Appears in: Mirage comics, Fred Wolf cartoon, Archie comics, 4Kids cartoon.
Ax Crazy: During his debut in both the Mirage comics and 4Kids series.
You Have Failed Me: Dregg is a lot more willing to punish failed subordinates than Krang or Shredder ever were, to the point of giving his right-hand man a Fate Worse than Death in the Season 10 premiere.
Other
Hamato Yoshi
Splinter's owner, a martial artist whose death at the hands of The Shredder gets the ball rolling.
Yamato Nadeshiko: Most notable in the 4Kids cartoon, where she's actually allowed to have lines and a semblance of a personality, but she is presumably one in other continuities as well.
Klunk
Michelangelo's pet cat, originally a stray that Mike found and adopted one Christmas.
Team Pet: Curiously enough, subverted. He's a completely normal cat who never gets involved in the stories and whose appearances are generally spent lying around on the floor or in someone's lap.
What Happened to the Cat?: When Shredder attacks April's apartment in issue 10, Klunk is nowhere to be seen, and isn't even mentioned when April, Casey and the Turtles escape. (This is doubly frustrating because he was explicitly shown to be in the apartment in the Leonardo special, which takes place immediately before.) He remains unmentioned for several issues before he shows up on Casey's farm with no explanation at all.
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