History Characters / TeenageMutantNinjaTurtles2003Allies

* KickTheSonOfABitch: Stranding someone on a frozen planetoid to die all alone in a far-flung part of outer space might seem inhumanly cruel, but given the many, ''many'' crimes Ch'rell committed against Utroms, mutants and humans alike, the Utroms are frankly being lenient when they do this to him.

* EarlyInstallmentCharacterDesignDifference: His child self in his debut episode looks like [[https://static.wikia.nocookie.net/tmnt/images/c/c3/MeetCasey-222.JPG/revision/latest/scale-to-width-down/1000?cb=20220504224756 a smaller version of his adult self]] complete with long hair. In ''The Lesson'', [[https://static.wikia.nocookie.net/tmnt/images/2/29/Young_Casey.jpg/revision/latest?cb=20210312093636 he has a different hairstyle]] and that [[https://static.wikia.nocookie.net/tmnt/images/0/0d/14vcbcvbcvbcb.jpg/revision/latest?cb=20140203165935 same design is reused]] for the flashback sequence in ''Dragons Rising'', which seems to be set at least a day or two earlier than the flashback from ''Meet Casey Jones''.

* NoCelebritiesWereHarmed: He's an obvious homage to Creator/JackKirby.

* RelatedInTheAdaptation: In the original comic, Dr. Dome and Ananda were not related, as the latter never had a father. Here, Ananda is Dr. Dome's daughter.

* {{Foreshadowing}}: If you look closely at Quarry's design, you may see that they havw long hair. This foreshadows [[{{Reveal}} the reveal]] that he, or she, is in fact a girl.

* InnocentlyInsensitive: Pairs with the NoSocialSkills below. He just says the first thing that comes to mind and gets confused when people, mostly April, get upset.

* OvershadowedByAwesome: He straddles the line between BadassNormal and this depending on the situation. Being an important friend and ally to the Turtles, Casey kicks all sorts of ass when he and his buddies are leaping from roof to roof, beating up Purple Dragons, Foot Soldiers, and your average Mooks. But when it comes down to battling against more powerful enemies such as Karai, Agent Bishop, the Triceratons, General Khan, and the Shredder, it's made painfully clear that Casey isn't really in the same league as the Turtles and the bigger, nastier villains. Usually, he gets taken out quite early on while the Turtles are able to battle the {{Giant Mook}}s, [[TheDragon Dragons]], and {{Big Bad}}s on more even terms.

* TheProfessor: He's obviously one. Gets a bit confusing in "Worlds Collide" part 1, where he interacts with Donatello and Fugitoid.

* GivenNameReveal: In "Return to the Underground", Quarry gets permanently cured and tells the Turtles her name: it's Sydney.

* TheWorfEffect: Gets casually swatted aside by the Triceratons (along with the rest of the Justice Force at the hands of their advanced weaponry) and the Tengu Shredder (who pulled a casual PunchCatch when Sentry attempted to attack him directly), despite being hands down the most powerful hero in the series.

* RecurringExtra: She never gets any dialogue or characterization, but appears in most of the Justice Force episodes.

* EstablishingCharacterMoment: In "Shredder Strikes" part 2, Leo gets cornered by dozens of Foot Ninjas. Suddenly, a Guardian jumps down and proceeds to kick the Foot's butt.

* MythologyGag[=/=]ContinuityCameo: In "Samurai Tourist", he is impressed by a New Yorker's outfit and gets his own set. He ends up looking like [[WesternAnimation/TeenageMutantNinjaTurtles1987 Rocksteady.]]

* LiteralMinded: When her arm gets injured and Donnie asks if she wants him to "look at it", she doesn't understand how looking at it will heal. Being an alien, it's {{justified|Trope}}.
* MiniMecha: She originally wanted to use a mech in her battle against Moriah, but it gets quickly wrecked by the Turtles in the beginning of "The People's Choice".

* MrFanservice: His default outfit is a sleeveless muscle shirt that show off his physique, and his abs are occasionally visible through his outfit. He is also TallDarkAndHandsome.

* PrimAndProperBun: She normally wears her hair like that, as she's very levelheaded and sometimes strict, though she also as a few silly moments (in "April's Artifact" where she gets ''waaay'' into the JunglePrincess role and "The Christmas Aliens" where she sticks a spoon on her nose and grins stupidly.)

!!!'''Voiced by:''' Creator/MarcThompson [[labelnote:Foreign [=VAs=]]]Thierry Janssen (FR)[[/labelnote]]

* AdaptationalIntelligence: His 1987 incarnation was never particularly bright, but this Leatherhead is easily the smartest incarnation of the character to date, rivaling Donatello's intellect (though he later confesses to being inferior to Don's smarts). Although, this is somewhat TruerToTheText as in [[ComicBook/TeenageMutantNinjaTurtlesMirage the original Mirage comics]], he nearly successfully created a transmat to reunite with the Utroms, which only failed because the Foot Ninja helping him had sabotaged the device.

* TruerToTheText: His [[WesternAnimation/TeenageMutantNinjaTurtles1987 previous series' counterpart]] was notably [[AdaptationalVillainy a villain]] who antagonized anyone he saw as weaker. Starting with this incarnation, Leatherhead would only antagonize the Turtles due to misunderstandings and quickly became their friend akin to the original comics.

* AdaptationalIntelligence: His past incarnations were never particularly bright, but this Leatherhead is easily the smartest incarnation of the character to date, rivaling Donatello's intellect (though he later confesses to being inferior to Donnie's smarts).
* AlwaysSomeoneBetter: Downplayed. He humbly admits that Donnie is his superior in regards to intellect, as well as conceding that Donnie did the majority of the work on the outbreak virus. He ends up being the Someone Better to ''Stockman'' of all people. Once he has access to Bishop's resources, he quickly develops a cure for the outbreak virus whereas Stockman was getting nowhere.

full-blown JunglePrincess and is able to take out the local giant hornets.

[[folder: The Professor]]

* MultiArmedAndDangerous: Fists has four very muscular arms and uses them to DropTheHammer with great force.

* MsFanservice: She's very pretty, comely and beautiful both in general and also thanks to her [[BareMidriffsAreFeminine outfit]], and other outfits in the series including her jungle garb during "April's Artifact". However thanks to her CharacterDevelopment, she becomes far more than just eye candy as the series moves on.

* {{Expy}}: He's the 2003 series' version of Professor Jordan Perry from ''Film/TeenageMutantNinjaTurtlesIITheSecretOfTheOoze'', albeit less nerdier and TheProfessor looking, wearing dark clothes instead over lighter colors such as donning a BadassLongcoat over a typical white lab coat and being more based on the [[WhatCouldHaveBeen initial depiction]]{{invoked}} of him revealed to be an Utrom before revising him to being a mostly human character.