History Flanderization / SpongeBobSquarePants

The characters of ''WesternAnimation/SpongeBobSquarePants'' underwent massive {{Flanderization}} after [[WesternAnimation/{{The SpongeBob SquarePants Movie}} the first movie]], with the show's tone and style of humor switching from innocently eccentric, gentle and witty to loud, aggressive, and deranged, with an increased emphasis on slapstick and gross-out humor.

During Seasons 6-8, the characters of ''WesternAnimation/SpongeBobSquarePants'' have undergone massive {{Flanderization}}. However, while mostly undone from Season 9 onwards, their flanderizations are still prominent in some post-Season 8 episodes. And even in the classic Golden Age Seasons, the show had is share of flanderization.

** In seasons 10-13, Patrick becomes a FatIdiot whose jokes mainly revolve around his random bursts of anger, constantly eating things that aren't food (including diapers and other peoples' mail), and being LethallyStupid to others. A good example is "Wallhalla", where his entire role consists of him barging into [=SpongeBob=]'s house, eating urchin poop (which he mistakes for raisins) out of his fridge, stealing a package from [=SpongeBob=]'s mother and flushing it down the toilet, and refusing to share his fresh Krabby Patty with a starving old man.

** His Flanderization, which was first noticeable in Season 4 and became really apparent in Season 6, turned him into a gratuitously obnoxious, moronic, deranged toddler as opposed to the zany, enthusiastic {{Cloudcuckoolander}} he was in the first three seasons. He became extremely hyperactive and over-emotional, with a higher-pitched voice, a shriller laugh, and a tendency to burst into tears far more often, and for longer ([[Recap/SpongeBobSquarePantsS7E10ADayWithoutTearsSummerJob there is even an episode about this]]). His treatment of Squidward became stalker-level creepy, his antics crazier and more dangerous and his mindset considerably more ignorant and childish to the point where any remaining trace of his adulthood vanished entirely and so he needs to have basic concepts explained to him. Even his facial expressions became much more exaggerated to make him come across as mentally unstable; many modern production images (such as DVD covers) depict him pulling enormous open-mouthed smiles with dilated eyes and large rosy cheeks.

** His second Flanderization, which was first noticeable in Season 5 and became really apparent in Season 6, turned him into [[TookALevelInDumbass one of the]] [[TheDitz dumbest cartoon characters]], [[LethallyStupid his actions even becoming dangerous at times]]. He has also [[TookALevelInJerkass taken multiple levels of jerkassery]]. In earlier seasons, Patrick was [[KindheartedSimpleton a nice, funny and lovable dimwit]] who had his jerky moments, but it was hinted that he was just [[InnocentlyInsensitive too dumb to realize the wrongness of his actions]]. However, his jerkiness got much worse and became much more frequent, up to FatBastard territory, going by the way he treats [=SpongeBob=] and Squidward on several occasions. Here are some examples:

* [[Characters/SpongeBobSquarePantsSheldonPlankton Plankton]]'s IneffectualSympatheticVillain role, to the point where he is arguably more likeable than [[DesignatedHero his nemesis]]. His more general plans of causing destruction have become less apparent as his desire for the Krabby Patty formula has evolved into an obsession. His [[AIIsACrapshoot sentient computer 'wife']], Karen's DeadpanSnarker mannerisms have also been upped to eleven.
* Originally, Mrs. Puff was just a NoRespectGuy who didn't want to have to deal with [=SpongeBob=]'s bad driving. She was frustrated with his poor performance in her class, but genuinely wanted him to succeed and was generally nice to him outside of the classroom environment. Then she tried to ''murder'' [=SpongeBob=] in one episode after what she felt was the last straw (which apparently only lasted until the end). Since then, while she never goes as far as trying to kill him again, she still ([[DependingOnTheWriter if inconsistently]]) pretty clearly loathes him in or out of class.