These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The mockery of Toot's weight issues is absolutely ruthless.
This has been lampshaded a few times. In an early episode, Clara denies that she's just "the same joke over and over" and adds that they must be thinking of Toot. Then in the Spinoff Babies episode, the narrator describes her as "a one-dimensional fat joke".
The show does live by 'anything or nothing is acceptable to mock', and is pretty ruthless with all of it.
Acceptable Religious Targets: Clara's extreme devotion to Christianity is often used to make her a villain. The show could never decide if she was Catholic (she used rosaries) or Protestant (she listens to Kirk Cameron and believes in the rapture doctrine).
Alas, Poor Scrappy: Even though Clara became very Flanderized in the later episodes of the show, it was still surprisingly sad when her arms were chopped off and she was killed in the movie.
Base Breaker: Captain Hero. He essentially became the main character midway through season 2. Sure enough, he also became the most divisive character as a result.
Better on DVD: Much like Family Guy, this show's DVD version has raunchier scenes and lines and extended footage that had to be cut for time, content, and/or legal reasons, and, in a lot of fans' eyes, is worlds better than what Comedy Central (and, in some countries, MTV) airs.
Crack Pairing: The show made a point of pairing every single character in every possible combination over the course of the show. Don't believe it? Pick two characters. Any two. Over the course of the show, these two will kiss, sleep together, have a relationship, or be teased to Hell and back.
Creator's Pet: Even fans of the character admit that Captain Hero is used way too much.
One promo described them as "not just crossing the line, but throwing up all over it".
Cult Classic: This show has a very large cult following, especially on internet forums. Fans will often have entire conversations with each other using nothing but quotes from the show.
Dude, Not Funny!: Chances are you'll say this at some point. Spanky Ham has this reaction in-show upon seeing a cell full of racially stereotyped Native Americans, despite laughing at cells full of stereotypical Africans, Mexicans, and mixed "Asians":
Spanky Ham: Now, see, that's not funny. Those people got a raw deal.
Fridge Logic: Godzilla's cameo in which he accuses Ling-Ling of being a "Twinkie". He for some reason, is in the same studio Ling-Ling was giving his speech in. Another one: How the hell can he throw those paper cups with a literal handful of said paper cups and a tree with a sign? Not to mention, having an Improbable Aiming Skills to throw them at him?
And how the hell does Godzilla manage to give anyone crap about becoming American after 'Zilla?
Harsher in Hindsight: One episode has a Black Rhinoceros make an impassioned plea for people to change their ways before it becomes extinct.
Hilarious in Hindsight: Princess Clara insisting gay marriage will lead to Nazis riding dinosaurs. Now we have Dinosaur D-Day.
Presumably Clara wears purple because no other Disney princess was known for wearing purple. As of Tangled, Rapunzel takes that spot.
Remember the episode where M----- Mouse killed cartoon stereotypes for being politically incorrect? Well, three decades earlier, Terry Tsurugi was doing the same thing to similar live-action stereotypes for being hired guns to "those very nice people".
The character of Spanky is a lot more funny now that cheap, crude Flash-animated cartoons (that aren't online. Remember, Spanky has been described as "A crude, Internet cartoon who farts on retards," so back when this was made, Flash cartoons were mostly seen online) are popular.
In a couple of episodes, including the first one, Ling-Ling Mega Evolves.
Lampshaded in one episode where after yet another ruthless fat joke she screams "I'm not even that fat! I'm slightly overweight!"
Jerkass Woobie: Toot deliberately sets out to be "the bitch", after believing she can't be the sex symbol, but tends to suffer the most of the entire cast. She becomes more sympathetic as the series goes along.
Misaimed Fandom: The episode "Xandir and Tim, Sitting in a Tree" revolved around Hero creating an alternate identity named Tim, and in that character, having an affair with Xandir. Xandir/Hero shippers took the episode to mean that Captain Hero was secretly in love with Xandir, even though the episode's writer stated in an online forum that the point of Hero's masquerade was merely to get sex from Xandir without having to face any consequences.
Case in point, Wooldoor implanting false memories of Foxxy getting sexually assaulted when she was a little girl, which leads her down a Roaring Rampage of Revenge as she mercilessly slaughters the people she thinks were responsible save one. When a horrified Foxxy asks why Wooldoor would do something like that, he casually says psychiatrists implant false memories all the time to make people feel better about how horrible they are. He then makes Foxxy think she's a chicken to get out of any retribution, which then cuts to a song about how false and implanted memories are great.
Playing Against Type: Tara Strong (previously sweet, wholesome Bubbles and doing voicework on cartoons that were either strictly for kids or were for kids, but had a Periphery Demographic) as Princess Clara and Toot. This was something that Strong herself commented on, as the series was starting.
The Scrappy: Played with in the episode "Lost in Parking Space, Part 2". In a parody of Hostel, mall patrons are able to torture various hated cartoon characters, including Daria (for some reason) and, the king of all irritating cartoon characters, Scrappy Doo.
Screwed by the Network: Comedy Central refused to renew them for another season leading to the third season being the final one. What's more, when the creators wanted to give the show a movie, they wouldn't give them a better budget to animate it. Leading to the movie being done in flash, and it shows.
Seasonal Rot: To some fans, season three, due to Comedy Central stalling on airing episodes and the show going too far with its gross-out humor.
Excludie, the ninth housemate who is excluded from everything. Fanfiction often casts Xandir in this role.
Ling-Ling. Especially in the movie when he pines for Xandir but can't have him.
Woolseyism: The Latin American dub brings funny new names for the characters (Puerquísimo Chancho, Morocha Amorocha, Mueble O'Algo) and a more over-the-top dub and general feeling which enhances the series.