In any work of fiction, including Japanese anime, it's fascinating to find out exactly how a particular character became a hero or a villain. Few characters are born to be good or evil. Instead, most of them are influenced or shaped by the world around them. Becoming a hero or villain could also be a matter of survival, financial success, or even principle. And the transformation isn't always slow.

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Some anime villains are characters who gradually lost their way to the darkness, slowly and surely redefining themselves to become an evildoer. Other anime characters became a villain practically overnight, often by suddenly gaining new powers, making a life-changing decision, or having this lifestyle forced upon them. Many of the best anime heroes, in fact, became bad guys/girls in a matter of moments. One day, they're perfectly innocent, and tomorrow, they're a total villain.

10 King Bradley Gained The Philosopher's Stone & Turned Evil (Fullmetal Alchemist: Brotherhood)

fullmetal alchemist wrath

Six of Father's homunculus "children" were born as homunculi, starting with the shadow-like Pride, but the sword-slinging Wrath is a different story. He was made, not born, and the process of making Wrath was a quick one. In fact, it only took one injection of the Philosopher's Stone to create Wrath.

An unnamed young man was one of many trainee cadets to become King Bradley/Wrath, and a certain dark-haired fellow succeeded where all the other candidates failed. In a matter of moments, he was reborn as Wrath, ready to serve Father for all time as a villain.

9 Junpei Yoshino Gained Curse Powers (Jujutsu Kaisen)

Junpei Yoshino cries during Jujutsu Kaisen

Junpei Yoshino was constantly tormented at school, and the bullies loved to kick him around. Junpei had all but given up on school and mainstream society, and that made him highly vulnerable to manipulation at the hands of curses such as Mahito.

Junpei seethed with anger and resentment, and when Mahito powered him up, Junpei briefly embraced villainy. He attacked his classmates at school and even went after Yuji, but before Yuji got badly hurt, Mahito destroyed Junpei, which enraged Yuji even further.

8 Mello Ran Away One Fateful Day (Death Note)

Mello munches on a chocolate bar in Death Note

While the super-detective known as L is more like a protagonist than a true villain in Death Note, the rogue investigator called Mello is a different story. Given his association with organized crime, his habit of killing his henchmen, and his general bad attitude, Mello is a villain, and it all started the day he learned of L's death.

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On that day, Mello and Near went separate ways, with Near remaining at the orphanage while Mello resolved to run away and do things his own way. It's heavily implied that his life of crime started then and there, and he only got worse over time.

7 Rindo Kobayashi Opted To Join Azami Nakiri (Food Wars!)

Rindo Kobayashi 3

In the anime Food Wars!, most chefs are defined as villains if they are aligned with obvious antagonists like the suit-wearing Azami Nakiri or his rogue son, Asahi Saiba. At first, the Council of Ten's members were neither good nor evil, but when Azami took over, all that changed.

Several Council members joined Azami's new organization, Central, and thus became villains who expressly approved of Azami's villainous ways. That included the former Council's #2 student, Rindo Kobayashi, who had no problems with Azami and his ways. Just like that, she became one of Soma's worst enemies.

6 Sasuke Uchiha Embaced Villainy One Night (Naruto)

Sasuke Uchiha Has Large Reserves Of Chakra

Under the surface, Sasuke's descent into villainy was a gradual one, with Sasuke inching closer and closer to abandoning Team 7 to seek greater power elsewhere. However, he didn't openly become an official villain until he ran away from the Hidden Leaf Village with the Sound Four's members to escort him.

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That marked the beginning of Sasuke's villainous character arc, and he only got darker from there. Sasuke narrowly fought off Naruto Uzumaki, who had gone after him, then walked right into Orochimaru's open arms to gain that much-desired power at last.

5 La Brava Became Gentle Criminal's Sidekick One Day (My Hero Academia)

La Brava from My Hero Academia.

It seems some villains were always rogues or criminals, such as the thuggish Muscular or the insidious Mustard. Other villains didn't embrace the life of crime until one particular day, and such was the case for the young lady known as La Brava.

La Brava felt all alone, and then one day, she stumbled upon Gentle Criminals' YouTube-based criminal career and was inspired. La Brava packed her bags and rushed off to meet Gentle, then became his official villain sidekick just like that. It was a pretty sudden decision, but La Brava didn't regret it for a moment.

4 Inca Kasugatani Joined A Cult (Fire Force)

Inca eyes glowing

The pink-haired girl known as Inca was never exactly a hero to begin with, but even as a borderline criminal rogue, she wasn't quite a full-blown criminal. She was just a punk messing around with her Ignition ability, but then the fire soldiers and Cult of the Ashen Flame both showed up.

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Both sides urgently wanted to recruit her as one of the Pillars, and Inca made her decision. For the sake of her personal freedom, she sided with the Cult, thus becoming a proper villain in a matter of seconds. She was soon seen wearing a Cult-style outfit, confirming her as a newly minted villain.

3 Kyo Ethnina Was Reborn In Another World (The Rising Of The Shield Hero)

shield-hero-kyo-ethnina-villain

When a person gets isekai'd into another world, they might become a hero or villain right away, depending on their new powers, if any, and their personality. Characters like Rimuru Tempest became heroes right away, but Kyo Ethnina went in the opposite direction.

Kyo was a bad-tempered gamer in Japan, then got reborn as Kyo Ethnina, who had stolen the Book Vassal Weapon. It's like he was reborn to be a villain, and he abused and tormented everyone around him until Naofumi finally put a stop to his rampage. This time, Kyo will stay dead.

2 Griffith Became A Villain With Two Words (Berserk)

Berserk's Griffith

Like Sasuke Uchiha, the supervillain Griffith's descent into villainy was both gradual and sudden. Deep down, he was always planning to become a great king by any means necessary, and he was a selfish schemer by nature. But that made him an antihero up to a point.

Then, on the fated day, Griffith told the God Hand's members "I sacrifice," sealing the fate of his friends and cementing his status as a villain. Griffith was reborn moments later as the winged, armored Femto, and he has never looked back.

1 Tsukasa Shishio Turned On Senku In An Afternoon (Dr. Stone)

Tsukasa Shishio in Dr. Stone.

Tsukasa Shishio the fistfighter was not evil in his 21st-century life, but he was certainly bitter and jaded about the world's unfair, oppressive nature. Now, in the new Stone Age, Tsukasa thinks he can destroy most of the statues and only let the pure youths be revived. That puts him at odds with the scientist Senku Ishigami.

In one afternoon, Tsukasa revealed his true intentions, and the two friends suddenly became enemies, just like that. Tsukasa even tried to kill Senku, but Senku secretly survived to fight back with science later. Tsukasa, meanwhile, wouldn't get redeemed until after he lost the Stone Wars.

NEXT: 10 Anime Villains That Died Peacefully