Whether it's a character not being who they say they are, the real culprit in a mystery, or just a general turn in a story, well-written anime plot twists have often changed the entire course of the anime itself.
Here are a few plot twists that completely changed the nature of the stories told in their respective anime.
Note: Spoilers abound for all anime discussed. The entire article is only the author's opinion.
Eight anime plot twists that change their anime's nature
1) "Children of the Prophecy" - Naruto
Much as Naruto and Shippuden are beloved by many fans worldwide, there is a snafu in the Children of the Prophecy plot twist first mentioned three-quarters of the way through Shippuden. It changed Naruto's story entirely, not precisely for the better in many fans' eyes.
The plot twist is as follows: a prophecy by the Great Toad Sage stated that one day the reincarnations of the Sage of the Six Path's sons Indra and Asura would show and hold the fate of the world in their hands. This just so happens to fall on Naruto Uzumaki and Sasuke Uchiha. They fulfill it by sealing Kaguya and ending the Curse of Hatred and the Infinite Tsukuyomi following the Shinobi World War.
This prophecy and the concept of destiny being involved in the story contradicted the first half of Naruto's story. The original series had the main characters, especially Naruto, going against the concept of destiny or divine fate that everyone is tied to and decides people's futures. Introducing this concept, especially that late into the series, completely undid the entire point of Naruto trying to become Hokage and, for some fans, revoked his underdog status.
This plot twist also made Naruto into a cosmic Cain and Abel story of redeeming the past mistakes and generational trauma, rather than the straightforward underdog story it was going for. It was considered a good move as far as breaking the cycle of hatred, but many fans felt they could've done so without the prophecy element being introduced.
2) "Aliens, Revolutions, and sisters?!" - Kill La Kill
In one entry, the three flavors of plot twist fit Studio Trigger's Kill la Kill, an already bombastic and over-the-top anime. The plot twists start flying fast and furious as of episode 13, when the wicked Nui Harime debuts, but the real heavy hitters don't start until episode 16.
The twist starts with Senketsu and the rest of Life Fibers being aliens, traveling from world to world to incubate/birth more of themselves and then destroying the planet to spread more across the stars. Senkentsu was explicitly designed to destroy life fibers. This answered the mystery of what Setketsu was, at the very least.
The second and third are much more involved. Satsuki was revolting against her abusive mother Ragyo for all her crimes against humanity with the Life Fibers, killing her father, and disposing of her little sister due to incompatibility with the aliens. That little sister is Ryuko Matoi.
This changes things for Kill La Kill quite a bit, going from a rebellion against an unjust system to expanding outward into a cosmic horror story while remaining an overall rebellion. Following the defeat and death of Ragyo and the life fibers, Honnouji Academy is destroyed, and the system is broken when Satsuki lays down her sword.
3) "The World Beyond the Walls." - Attack on Titan
Attack on Titan went from a survivor-story-against-impossible-odds to sins-of-the-father-story last season in a rather abrupt change. Though some fans have stated they saw it coming, others were blindsided by it and decried it as lousy writing to introduce such a game-changing plot twist so late in the anime.
To summarize the plot twist: Paradis island is home to people called Edlians, who bargained with the Titan Ymir in ancient times and oversaw an empire of bloodshed against the neighboring nation of Marley, and the main characters are descended from Eldians. They were driven to Paradis as punishment by Marley. This twist shatters Eren's mind and sends him into darker places.
Rather than stand in defense of Paradis after driving the last hostile titans out, Eren and company decide the best course of action is to wage war against Marley and later the entire world (or at least Eren, everyone else tried to find peaceful solutions to the problems). This results in the genocidal Rumbling plan that has only recently begun in the anime.
This plot twist completely turned Attack on Titan's story on its head. Heroes like Eren turned villainous; the audience was forced to grapple with the implications of what several generations of hatred could do. There stopped any notion of survival when Titan Shifters came into play, and the war began in earnest.
4) "The end of the Beginning." - RWBY
A plot twist that fundamentally changed how a show was seen and experienced is RWBY's multiple plot twists during Volumes 3 through 6. While the show has millions of fans worldwide and is highly successful, to the point where a spinoff anime is coming later in 2022, the big plot twists of the end of the Beacon Arc (and even into the Atlas arc) still ripple across the show and fandom.
Volume 3 had a school setting called Beacon Academy, getting attacked and ravaged by the main villains in a surprise attack. It also saw the deaths of notorious criminal Roman Torchwick, Beacon Headmaster Ozpin, Atlas android and prospective Beacon student Penny Polendina, and tournament champion Pyrrha Nikos. Following this traumatic event, lead protagonists Team RWBY were scattered to the four winds of Remnant. The actual main villain, the immortal witch Salem, made her debut at the end of this volume.
Subsequent volumes would flesh out Salem and her main league of cohorts and minions, including Cinder Fall, and likewise to the characters and world. Previously hinted at plot items, the Maidens, in particular, became highly important. The backstories of the main characters and villains were gradually expanded upon, including Salem's being intertwined with Ozpin's as a Romeo and Juliet story in ancient times and Weiss' actual abusive family situation coming to light.
The story's twists and turns since Volume 3, coupled with the increase in backstory and slower paces of Volumes 4 and 5, aided RWBY in becoming much more than the simple story of school shenanigans it started as. While this evolution was slow going, it made RWBY much better as the writing got tighter and the show evolved into more of a more extensive fantasy adventure series akin to Lord of the Rings.
5) Stands replacing Hamon - JoJo's Bizarre Adventure
Stands replacing Hamon in Jojo was already enough of a plot twist to warrant an entry. It catapulted a relatively unknown series into the mainstream. It changed the nature of JoJo from being a series about fighting vampires to being about spirits and fighting other people that controlled said spirit, hereafter known as Stands.
While this may not seem like a plot twist, the actual origin of stands is. According to Diamond, Stands are Unbreakable and later Golden Wind, bestowed upon people hit by a Stand Arrow made of material that comes from space.
Fundamentally, the introduction of Stands and pushing Hamon to the back already changed the series by adding a new power instead of vampirism vs. sun energy. The last vampire Dio was dying in Stardust Crusaders ultimately marked the end of the earlier Jojo story where it was a horror show and into a more hot blooded type show.
While the horror never truly fades, Stardust Crudasers' introduction of Stands changed the nature of the show. Instead of vampirism being the primary source of horror, it's now human nature combined with spirit control. Jotaro has become one of the iconic characters to show up more than once.
6) Darker magical girls - Peulla Magi Madoka Magica
The first Madoka plot twist comes when Mami dies by getting her head chomped by a witch, marking that it's a different type of magical girl anime series. This catapulted and turned the series darker, and it was only episode 3.
Plenty of plot twists fundamentally changed Madoka, but to put one of the major ones into perspective? Homura being stuck in a time loop changed the series from a fun magical girl series, into a depressing horror, into a tragedy. This one hurts to rewatch, knowing where it's going and how long Homura's tried to be with Madoka.
It just put everything in perspective and further changed the series' nature. It shows that Madoka isn't the only one suffering and Homura has such "main character" syndrome that she decides to break time and mess everything up to get Madoka back. The Rebellion movie further highlights just how messy things are.
It makes everything feel very tragic at the end of the anime. However, it uplifts everything by having Madoka become a goddess and end the system or at least aid magical girls into the afterlife.
7) The Saiyan twist - Dragon Ball/Dragon Ball Z
From Dragon Ball to Z, the Saiyan plot twist changed Goku's journey. Dragon Ball itself had been quite the lighthearted adventure, even with King Piccolo's intervention. The Saiyan twist in Z made everything much more scaled up.
Goku was revealed to be an alien and had a brother who was likewise. It also explained the Great Ape transformation and fundamentally made Dragon Ball a series primarily about fighting more brutal fighters and monsters who could destroy planets. The furtherest in destruction the original Dragon Ball ever went was destroying the Red Ribbon Army Base.
This further changed in Dragon Ball Super, wherein gods and other monsters were introduced. Dragon Ball Z set the tone for all the power scaling that would happen, from the earliest plot twist of Goku's brother being evil and an alien. It catapulted things to the next level.
8) Card games decide everything! - Yu-Gi-Oh!
The card games component was in Yu-Gi-Oh! toward the tail end of the first manga arc. It wasn't there throughout. What was there were usually many more gruesome games and penalties that sometimes led to death.
The card games replacing everything catapulted Yu-Gi-Oh! into the mainstream, but also lost a lot of the darker aspects. It made the series more sanitized and gave more character development opportunities, such as Seto Kaiba making a long redemption arc.
Subsequent seasons would focus primarily on the card game element, as it became a franchise staple. It helped that Yu-Gi-Oh! also made waves overseas in the card game, so it's no wonder that the card game took priority over everything else.
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