History Characters / TeenageMutantNinjaTurtles2003Allies

* SecretTestOfCharacter: During the "Shredder Strikes" two parter, the Guardians are monitoring the Turtles, seeing if they will accept Shredder's offer and join the Foot. When they discover that they rejected, a guardian helps Leo in a battle and introduces himself.

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

--> Voiced by: Pete Zarustica

--> Voiced by: Liza Jacqueline

* HotBlooded: So much so that even Raphael has been disturbed by it on occasion.

* BatterUp: Often wields a bat as well as his signature hockey puck.

* BigDamnHeroes: Gets to do this occasionally.

* {{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 Goongala!

* MaskPower: When going into action, Casey usually wears an old-style hockey mask.

* NoSocialSkills: Due to his only focus being to get stronger and take down bad guys most of his life, he's not very well-versed in manners or even basic etiquette. A few of the first interactions with the turtle, and especially April, have him getting on everyone's nerves for never taking a hint or watching what he says.

* VigilanteMan: As he grew older, Casey became a vigilante and started hunting down crooks — particularly Purple Dragons — in the streets. until he meet Raph.

* JerkWithAHeartOfGold: He can be an insensitive {{Jerkass}} at times, but still has a heart and is loyal to his friends. Most of his rudeness stems more from having NoSocialSkills than being inherently a jerk.

* JerkWithAHeartOfGold: All versions have him being a jerk to at least one of the heroes, but they all still have a heart.

* AdaptationalAngstUpgrade: He was given a tragic backstory (See DarkAndTroubledPast below) that his original [[ComicBook/TeenageMutantNinjaTurtlesMirage Mirage comics counterpart lacked]] (it's especially jarring considering Eastman and Laird originally conceived him as someone who became a vigilante because he watched way too many "bad cop" shows instead of the usual "someone killed his family" origin). This backstory, however, was adapted in the comics later onwards.
* BadassNormal: The only member of the team who has never had any mutant powers or abnormal origins in any continuity. Ninjitsu also doesn't rub off on him the way it does on April.

* {{Metamorphosis}}: From alligator to humanoid alligator everywhere else.

* [[CoolBigSis Cool Big Sibling]]: 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.

* [[CoolBigSis Cool Big Sibling]]: 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.

* YouCantGoHomeAgain: Leatherhead initially yearns to rejoin the Utroms.

* AdaptationalAngstUpgrade: He was given a tragic backstory (See DarkAndTroubledPast below) that his original [[ComicBook/TeenageMutantNinjaTurtlesMirage Mirage comics counterpart lacked]]. This backstory, however, was adapted in the comics later onwards.

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* TheBerserker: Initially.

* IKnowMaddenKombat: Casey uses sports equipment as his main weapon.

--> Voiced by Veronica Taylor

--> Voiced by Marc Thompson

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

--> Voiced by Pete Zarustica

--> Voiced by

-->Voiced by Jason Griffith

* {{Leitmotif}}

* [[CoolBigSis 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.

* UnfazedEveryman: After her intial scream and/or faint upon meeting the turtles she becomes this.

* [[CoolBigSis 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.
* DarkAndTroubledPast: 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.
* EmbarrassingFirstName: Arnold. Casey is his middle name.

* YouGottaHaveBlueHair: Has black-blue hair.