Body Horror: In one of the early episodes, Fergy Fudgehog at Pinata Central, accidentally runs into an random acquaintance (a Macaraccoon) just returning from a party, his body is all smashed up is missing an eye revealing a large empty socket, and his mouth is unattached to his body. Yet the dismembered Macaraccoon doesn't mind at all and casually says through his disembodied mouth "Hey Fergy, how are you doing? Going to a party?". This is the reason Fergy doesn't like parties.
Disguised in Drag: Paulie, Franklin and Fergy in the episode "Beauty And The Beasts."
Drunk with Power: Fergy as Piņata Wrangler in "To Catch a Piņata," so much so he tried to fire his best friend off to a party just to cement his position.
Paulie: Fergy, what's gotten into you?!
Fergy: Ambition, lamb chop! I've tasted power, and I like what I'm mashing!
Easy Amnesia: Averted with Ella Elaphanilla, who's amnesia is not a plot device but a full-time trait, as well as the fact she has anterograde amnesia in addition to retrograde amnesia.
Played straight on Pester in "Pester the Piņata," which causes him to think he's a baby piņata. At the end he actually rapid-fires between this personality and his normal self due to a series of slaps. And at the end he ends up thinking he's a Ruffian.
Enemy Mine: It's a rare occasion when Pester and/or the Ruffians team up with the piņatas for something, but it happens.
Boris: "Boys, meet your new neighbor, Associate Associate Associate Professor Poofter!"
Professor Pester: "That's Pester!"
While understandable due to being piņatas and all, some really express an S&M-esque joy at being beaten. Perhaps best demonstrated at the beginning of "Pester the Piņata" where Hudson shows them the newest stick and Franklin immediately asks who'd want to go to town on him with it.
Numerous moments in the episode "Crimes of Passion Fruit". The scene in which Fergy looses it resulting in him destroying the fruit bowl of the Big Boss in certain frames is cut to look like something reminiscent of a slasher film. He then panics, ingesting the "remains" but not before conversing with himself in a manner made to look like he's lost his mind and is talking to another side of a split personality. The entirety of the episode is then Fergy attempting to hide what he had done, not realizing that there was a speaker in the fruit he ate to channel the voice of "The Big Boss", convinced he's possessed by the vengeful spirit of the man who he'd done in. He runs to the Bonboon, who suggests an exorcism of all things! One has to admit—for a 4Kids-produced cartoon, this was pretty dark...
And then of course: "What's with all the heavy breathing? Are you some kind of sicko?"
In the episode that introduced the Big Boss: "I want you to look me in the grapes."
Paulie once acted as a distraction by dressing up as a balloon stripper. (Seriously!? How did they get away with that?)
I'm a Humanitarian: Just like in the games, the Piņatas have no qualms eating candy regardless of whether or not it's currently being bled (or in one case, sneezed) out of someone else.
The subject is explored in the appropriately-titled episode "Candibalism" where Fergy receives his order chocolate bunnycomb and poses it as his "cousin Candice" so he can selfishly keep others from eating the treat. When he finally gives in and devours the chocolate bunnycomb, everyone assumes that Fergy just committed an act of cannibalism, complete with him being muzzled and wheeled on a straitjacketed handcar a la Hannibal Lecter.
Franklin feeds Sour Mongo fried Cluckles drumsticks.
The Last Straw: In "Candiosity," an overstuffed Fergy on the scanner eats one last piece of candy, causing his top to burst off and completely empty him, saving him from being launched to a party at the last second.
Lighter and Softer: In the original game Professor Pester permanently Mind Raped Stardos into the deranged psychopath Destardos with his family never finding out the truth assuming he had died. In the show Pester is a majorly laughable villain who's patheticness rivals Doofensmirtz.
Low-Speed Chase: One episode features a chase on really slow moving forklifts.
Metaphysical Fuel: In "The Wrong Stuff," Pester's spaceship is fueled by magnetism. When that runs out, the piņatas manage to refuel the ship using Hudson's magnetic personality. When they need anti-charm in the reversed universe, they use Pester's personality instead.
Never Say "Die": Surprisingly averted, given this is a 4Kids production. The episode "I, Pretztail" gets away with the use of the words suicide, death trap and two uses of killed in the space of a minute.