* SugarWiki/AwesomeMusic: Much like Hartman's other [[WesternAnimation/TheFairlyOddParents two]] [[WesternAnimation/DannyPhantom shows]], the [[https://www.youtube.com/watch?v=bI6Csyf0ECw intro for this series]] is high energy and very well produced with a unique jazz sound to it.
* BaseBreakingCharacter: Dudley. Some find him funny and endearing thanks to him being voiced by Creator/JerryTrainor of ''Series/ICarly'' fame, others find him obnoxious and intolerable. It's generally agreed upon that Kitty is the better protagonist between the two.
* DracoInLeatherPants: Madame Catastrophe gets this very often in the fandom. Dr. Rabies does not, generally being [[RonTheDeathEater turned into pure evil]].
* EnsembleDarkhorse: Madame Catastrophe and Dr. Rabies.
** Little Chipmunk Girl
** Tammy the secretary.
** Daisy, Dudley's girlfriend from "Girlfriend or Foe".
** The Fiendish League of Potential Perpetrators (F.L.O.P.P.)
** Kitty's mom, even though she only ever appeared in a short flashback and as one of the Chameleon's disguises.
* HamAndCheese: Even those who hate the show can't help but laugh while Snaptrap [[ChewingTheScenery chews the scenery]].
* HilariousInHindsight: In "Mission: Really Big Mission", when the Chameleon introduces himself to D.O.O.M., telling them he does impressions at the Chuckie Hut every other Friday night, he morphs into a look-alike of [[Franchise/KungFuPanda Po the Panda]]. Twelve years later, ''WesternAnimation/KungFuPanda4'' would feature a shapeshifting villainess called the Chameleon as its main antagonist.
* HoYay: Dudley and Keswick even share a "Lady and the Tramp" kiss in "Law and Odor".
** There's also the time that Bird Brain shot Dudley with a love ray in "Love Bird".
* IAmNotShazam: Dudley is only referred to as ''T.U.F.F. Puppy'' in nickname form by Kitty and that's only once and it was said sarcastically.
* MorePopularReplacement: Daisy is better well-received as Dudley's second girlfriend in her episode than Becky due to her more adorable design, adorably ditzy, chemistry with Dudley due to their [[BirdsOfAFeather similar mindsets]], and voiced by Creator/TaraStrong doesn't hurt.
* MoralEventHorizon: Jack Rabbit betraying Kitty and T.U.F.F.
* OlderThanTheyThink: A wolf popstar that Kitty's a fan of is named [[Music/JustinTimberlake Justin Timberwolf]], as mentioned in "Booby Trap." ''WesternAnimation/TheSimpsons'' had already named Maggie's wolf plushy that in the episode "Midnight Towboy."
* PlatonicWritingRomanticReading: Although in theory Kitty and Dudley's relationship is platonic, the sheer amount of Ship Tease has led many viewers to interpret it as romantic, and even when they both have love interests on separate sides, these love interests give the impression of being actually RomanticRunnerUp to Kitty and Dudley's relationship.
* PeripheryDemographic: [[PopularWithFurries Among the]] UsefulNotes/FurryFandom.
* TheScrappy: Becky from "Love Bird" isn't well-liked due to her bland personality and ugly design.
* StrawmanHasAPoint: Kitty was pretty much against working with Dudley and tends to still be from time to time. Given what [[LethallyStupid Dudley]] does from time to time, it isn't unreasonable.
* SuspiciouslySimilarSong:
** Compare this show's theme song with that of ''WesternAnimation/TeenTitans2003'', there is a similarity in the rhythm.
** Given the spy theme of the show, the song sounds vaguely similar to ''Secret Agent Man''.
* ToughActToFollow: Being Hartman's first new project since ''WesternAnimation/DannyPhantom''. Unfortunately, it never could reach that show's level of reception by viewers.
* UglyCute: The Chameleon is considered this for some fans.
* UnfortunateCharacterDesign: Becky's design has drawn [[https://twitter.com/hauntedpaw/status/1359256590562570240?s=21&t=YO9pbFyUdGL8PKEybYtzFQ much ire from viewers]], as the lighting on her nose unintentionally makes it look like she has a big hole in her face and her mouth is so far to the side of her face it's directly underneath her eye.
* TheWoobie: Kitty Katswell. Her status as TheChewToy at T.U.F.F. goes hand in hand with this. Her AmusingInjuries are usually funny, sometimes though: [[http://www.imgur.com/MrdGv1X oh poor Kitty.]]
** Dudley has his moments too, even if you consider him a gigantic nuisance at times.
** JerkassWoobie: The Chameleon pretty much lives and breathes this trope. It's played for laughs, as he's supposedly nasty thanks to being depressed about being alone, but half the reason he's alone is because he's such a nasty guy in the first place. [[spoiler: It's not played for laughs when he almost gets T.U.F.F and D.O.O.M to destroy each other and the entire city by tricking them into destroying the city/their "bases," sharing an office, and watching as a real estate agent.]]
----