Needs a Better Title There are many reasons why tone of the story may change. Sometimes happy, joke-based, show goes into much serious, and darker direction. Sometimes once dark and deadly serious series turns into a comedy. Sometimes it completly changes the genre. Sometimes writers run out of ideas and just try to put anything they can or exact opposite they finds what they really want to do. Sometimes Executive Meddling or Creator Breakdown takes story into new direction and turns into something completely unrecognizable from it's source material. And sometimes all of it at the same time. Or none. Cerebus Rollercoaster is what happens when Cerebus Syndrome gets Zig Zagged series goes back and forth through different tones, jump from genre to genre or dance on Sliding Scale of Idealism vs. Cynicism. Like rollercaster it rides ahead, repeatedly going up and down. Sometimes whoever, rollercaster may crash in that case series ultimately grown the beard, absorbing best elements of all phases it went through and evolving into something completely different. Of course, it can always goes back on track, if something will force the change to be undone This may occur for different reasons. Sometimes creators just plain don't know what exactly tone they want to give their work. Maybe story went too far into Cerebus Syndrome, and writer is tired and horrified of Crapsack World it become, but while trying to reverse the process, he finds out that new, Darker and Edgier settings have a lot of fans, so he desperately tries to balance drama and comedy to keep both fanbases happy. Sometimes new writer decides to take series in new direction, next one into another and so on, until fans grown to be writers themselves and take series to it's righteous rots. Some people may just Follow the Leader too much, and when leader changes, so does direction of their story. And sometimes they just doesn't want to stick to one setting and being forced to discard all story ideas who are too dark or too light for basic settings. Tropes Are Not Bad, and so is this when played right, it may give series unique, recognizable style and keep it fresh. If done badly, however, will pretty much turn story into a train wreck. Compare Mood Whiplash. The difference is that Mood Whiplash is more under creator's control and can often happen during one story arc, whileCerebus Rollercoaster rather apply to mood shifting between story arcs and whole process being far less planed and controlled, if at all.
Examples:Anime & Manga
- Gundam franchise as whole goes through this, with series varying from Zeta Gundam to Gundam ZZ, to G Gundam to Victory Gundam, from Gundam Wing to Gundam SEED to Gundam00.
- Tengen Toppa Gurren Lagann in a way that mirrors rollercoaster ride taken by entire mecha anime genre through it's history. Episodes one to eight are very optimistic and often outright comedic, taking a lot from classic 70's Super Robot anime like Mazinger Z or Getter Robo. Next episodes on the other hand contains their share of angst and dark themes, and villains, while still evil, gaines some deepth. It mirrors effect Mobile Suit Gundam has on the genre. Later episodes are post Neon Genesis Evangelion era, being much darker than before, with a lot of different moral values here and there. Yet, in both parts anime remains pretty epic and in last part takes epicness Up to Eleven, mirroring efects GaoGaiGar and other reconstructions had on mecha genre. it seems that this show is traying to tell that it doesn't matter what tone or message your mecha show has - if it doens't have it's share of epicness, you're doing it wrong.
- Entire Super Hero genre went through this. Golden Age was pretty dark Bat Man was gun-wielding Vigilante Man, Wonder Woman was Heroic Sociopath who liked to tie her enemies and lot of heroes has no problem with killing criminals, especially Those Wacky Nazis. Silver Age was a result of Reverse Cerebus Syndrome when everything became Lighter and Softer, sometimes to just ridiculous levels. Bronze Age was step towards more serious direction, which was taken way to far in Dark Age. In result, in Modern Age, everybody said screw it and does whatever they wants, so the same company can publish adventures of Incredible Hercules and The Punisher or Power Girl and Justice League: Cry For Justice.
- Every time new writer takes over ongoing series or takes care of certain character, you can expect him to take it into new direction, with often mixed results. It's hard to find Super Hero who didn't had this happening to him.
- Sometimes it may happen even without changing the writer, because he (or somebody else) decides that character needs retool,
- Johnny the Homicidal Maniac started as black comedy, gone serious in fourth and fifth issue and then jumped back to black comedy.
- Power Rangers. It always is and will be a show nobody can take without a lot of Willing Suspension of Disbelief, campy and Crazy Awesome in it's own way, but tone of each season varies. Lord Zedd was it's Knight of Cerebus and set much more epic arc, than Rita arc. Both Power Rangers Zeo and Power Rangers Turbo were step down from serious towards lighter tones, only for series to turn into epic space opera during Power Rangers in Space and Power Rangers Lost Galaxy. Tone of the series can vary from dark, like Power Rangers Time Force, to completely comedic, like Power Rangers Ninja Storm. Even checking out source Super Sentai material isn't any indication of which route next series will take, as proven by darkest series of all, Power Rangers RPM, which was based on self-parody of Super Sentai.
- El Goonish Shive has this problem when it went through Cerebus Syndrome, it ended being too dark in Painted Black arc, so author took it back to being silly and fun, but decided to introduce serious from completely different angle, adding a lot of relationship driven plot points, teenage angst and Slice of Life elements. Ultimately series evolved into combination of comedy, teen drama and epic awesomness.
- Atop the Fourth Wall, while is always deeply comedic series, has plot arcs toned to fit the main villain funny villains are just for addinational jokes, while serious ones tends to have some plans going in the back. Comedic and incompetent Doctor Insano was replaced by really scary Mechakra. After Mechakra's defeat, his place was taken by Harmless Villain Doctor Linksano, to let fans catch a break. Currently Linksano has been replaced by far more menacing Lord Vyce. Of course each arc is full of episodes completely unrelated with it's plot, which helps keeping straight main purpose of the show.
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