Character derailment

Character derailment is the opposite of character development. Instead of learning from mistakes, they just get worse.

It is not to be confused with Flanderization, as it involves over-exaggerating and amplifying a character's trait(s). Character Derailment, on the other hand, refers to a character's trait(s) becoming vastly different compared to what was previously shown.

Notable Characters Who Suffered Character Derailment

 * Fonzie (Happy Days; Season 4-11; He is the trope namer for Jumping the shark, which he literally did in the episode Hollywood Part 3. This is character derailment because in Season 2 he got hurt)
 * Kai (mh:besttvshows:LEGO Ninjago: Masters of Spinjitsu; Seasons 8-12)
 * Henry Hart/Kid Danger (mh:terribletvshows:Henry Danger)
 * Ray Manchester/Captain Man (Henry Danger)
 * Charlotte (Henry Danger)
 * Jasper (Henry Danger)
 * Piper Hart (Henry Danger)
 * Danger Mouse (2015) (mh:besttvshows:Danger Mouse (2015))
 * Sasuke Uchiha (Naruto Shippuden)
 * Obito Uchiha (Naruto Shippuden)
 * Madara Uchiha (Naruto)
 * Yuuki Terumi (BlazBlue series)
 * Nana (Elfen Lied)
 * The Thunderman Family (The Thundermans)
 * Dawn Harper (Nicky, Ricky, Dicky, & Dawn)
 * Daffy Duck (Looney Tunes; DePatie Freleng/Seven-Arts Era)
 * Spongebob Squarepants (SpongeBob SquarePants: Seasons 6-8)
 * Patrick Star (Spongebob Squarepants; Seasons 6-8)
 * Mr. Eugene Krabs (Spongebob Squarepants)
 * Cosmo Cosma (The Fairly OddParents; Season 9-10)
 * Carl Wheezer (The Adventures of Jimmy Neutron: Boy Genius)
 * Sheen Estevez (The Adventures of Jimmy Neutron: Boy Genius/Planet Sheen)
 * Discord (My Little Pony: Friendship is Magic; Season 9-He had a logical development of becoming a good guy, until it was revealed that he was Grogar all along. He on that way put the whole world in danger as he made the terrible trio very powerful that even he couldn't deal with them, which just goes against his whole development)
 * Jonesy Garcia (6teen)
 * Caitlin Cooke (6teen)
 * Jude Lizowki (6teen)
 * Eddy (Ed, Edd, n Eddy; Season 5-6)
 * Ed (Ed, Edd, n Eddy; Seasons 5-6)
 * Sarah (Ed, Edd, n Eddy; Seasons 5-6)
 * Jimmy (Ed, Edd, n Eddy; Seasons 5-6)
 * Kevin (Ed, Edd, n Eddy; Seasons 5-6)
 * Rolf (Ed, Edd, n Eddy; Seasons 5-6)
 * Johnny 2x4 (Ed, Edd, n Eddy; Seasons 5-6)
 * Lee Kanker (Ed, Edd, n Eddy; Seasons 5-6)
 * Marie Kanker (Ed, Edd, n Eddy; Seasons 5-6)
 * Numbah Four (Codename: Kids Next Door)
 * Hot Shot (Transformers: Cybertron)
 * Danny Fenton/Phantom (Danny Phantom; Season 3)
 * Inferno/Roadblock (Transformers Energon Season 3?)
 * Bumblebee (Transformers: Robots In Disguise 2015)
 * Ellie (The Last of Us Part II)
 * Lynn Loud Jr (The Loud House)
 * Light Yagami (Death Note)
 * Suzaku Kururugi (Code Geass)
 * Bob Bobowski (SMG4 Season 8)
 * Axol (SMG4)
 * Nino Arizugawa (Anonymous Noise; Had been growing a relationship with Yuzu (Even being kissed by him very often), only for her to turn him down and go back together with Momo.)

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