What's an action anime series without some kind of power up? Newer villains appear who are vastly more powerful than the last villain, which means the hero needs a way to catch up. Ideally, the power up or transformation happens through vigorous training, or a fight where the protagonist either loses someone close to them or realizes something about themselves to hit the next level they've had trouble getting to.

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But that doesn't happen with every power-up. Occasionally the story goes in a different direction, and a character just gets stronger with no explanation, or worse, a bad one. They don't have to put in any hard work either in combat or training--it just happens. When this happens, if the story isn't careful, it can trivialize an otherwise serious situation. But if it comes with an awesome fight afterwards, that can make up for it.

10 Kid Trunks Going Super Saiyan Left Even His Father Bewildered At How Easy It Was (Dragon Ball)

Trunks Kid Super Saiyan Cry

“I guess I’ll go...Super!” This was the moment a ton of Dragon Ball Z fans gave up on the Buu Saga. Super Saiyan was meant to be this crowning achievement for any Saiyan. At the time, Gohan was the only one capable of going Super Saiyan 2, and no one knew Super Saiyan 3 existed. Super Saiyan was the best most could do, and Trunks at eight years old seemingly achieved it off-screen and had mastered it with such little work that even Vegeta was unaware of it. Vegeta’s shocked reaction to his son going Super Saiyan tells the entire story.

9 Natsu Gained The Dragon Force Power As A Fluke (Fairy Tail)

Anime Power Up Transformation Natsu Dragon Force Fairy Tail

The power of Dragon Force is meant to imbue a Dragon Slayer with attributes closer to that of a Dragon. It's something only a handful of Dragon Slayers have ever shown, and the first time that Natsu reached this power was an accident. During his battle with Jellal during the Tower of Heaven arc, Jellal proved Natsu wasn't even in his league.

He thoroughly trounced Natsu, and there was nothing left for Natsu to do except die. Until, out of desperation, he started eating etherion--concentrated magic--to regain his magical power. This was supposed to kill him, because concentrated magic isn't meant to be consumed. But Natsu being the main character meant not only did it not kill him, he briefly attained Dragon Force, a power he used to defeat Jellal.

8 Star Platinum's Time Stop Wasn't Even Hinted At (JoJo's Bizarre Adventure)

JoJo Stardust Crusaders Jotaro Star platinum Time Freeze

Jotaro Kujo’s Star Platinum was introduced early in JoJo’s Bizarre Adventure: Stardust Crusaders, and of all the Stands the protagonists had, his was seen the most. It was very clear what his Stand could and could not do. And yet despite this, when Jotaro went up against DIO, he found himself in a tight spot. DIO’s The World Stand could stop time itself, meaning Jotaro had moments where he was defenseless. The only reason he survived was that Star Platinum randomly gained a brand-new ability mid-fight: Time Stop. Stands upgrading later became common, but at the time this felt entirely like it came out of nowhere.

7 Caulifla's Super Saiyan Form Was Gained With No Effort (Dragon Ball)

Dragon Ball Super - Cabba shows Caulifla how to transform

If Trunks going Super Saiyan wasn’t bad enough, Caulifla was somehow worse. Trunks' Super Saiyan transformation happened off screen—it’s easier to fill in the blanks in a scenario like that.

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But Caulifla's transformation happened in front of everyone, with Cabba explaining to her that it was like feeling a tingle in the back. Caulifla not only mastered Super Saiyan easier than Cabba, but she reached Super Saiyan 2 with no effort either. This didn’t stop her from being an awesome character, but it didn’t make any fans who weren’t hot on Super feel any better about it.

6 Ichigo Gained Power That Took Centuries To Achieve In Mere Weeks (Bleach)

Ichigo Kurosaki is using his bankai

With Bleach, nearly every power-up Ichigo ever got wasn’t really earned. Sure, he always went through some dangerous training to achieve it, but the fact that he was even capable of achieving it was ridiculous to begin with. Everything he achieved took the others decades and centuries to achieve, and he not only reached them, but surpassed them while he was still in high school. He was one of the coolest characters of the 2000s era of anime, but he was far too talented at skipping the line.

5 Fairy Tail's Second Origin Was Given To Help The Team Catch Up (Fairy Tail)

natsu-goes-through-second-origin-training Cropped

Second Origin literally is an unearned power-up. As the team got ready for the Grand Magic Games, they found themselves up against a time crunch. Unable to train seriously for any real time, Ur came along and offered them the chance to get stronger by utilizing Second Origin. Second Origin would unlock the potential inside of them to allow them to instantly get stronger, so long as they were able to deal with the effects. Within a day they were vastly more powerful and able to compete, showing off their power as Fairy Tail.

4 Yuno Gained Additional Magic Energy That Shouldn't Have Helped Him (Black Clover)

yuno black clover spirit power

During the Midnight Sun’s invasion arc, the organization turned many of the Clover Kingdom’s most powerful fighters against them. They implanted the souls of elves gone by into mages, and they would go from being Clover Kingdom humans to being loyal to the elven cause. There was one major exception to this: Yuno, who received the elven soul of a baby with no way to impose it’s will upon Yuno. Instead, Yuno experienced a massive power increase that allowed him to hang with all the other Magic Knight Captains with no drawbacks.

3 Naruto And Sasuke Were Given Powers From The Sage Of Six Paths (Naruto)

hagoromo, naruto, and sasuke

In the latter half of Naruto, both of the lead characters found themselves woefully under-powered against the series' antagonists. But that all changed when they met the Sage of the Six Paths, someone who had more than enough power to give out gifts to both Naruto and Sasuke.

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Sasuke was granted the Rinnegan, which gave him the ability to use space-time jutsu and teleport. Meanwhile, Naruto was given the Six Paths power. Both of them needed these to have a chance against Kaguya, but neither of them did anything to earn it.

2 Yusuke's Mazoku Form Was A Plot Contrivance To Make Him Into A Demon (Yu Yu Hakusho)

YuYuHakusho-1400-Mazoku-Yusuke

Yusuke fought his heart out against Sensui, but in the end he found himself defeated by the former Spirit Detective. That should have been the end, but the character was revived a second time, and gained a brand-new power too. Yusuke learned he was the descendant of one of the strongest demons in the Demon World, and with that power he was able to fight Sensui evenly and gain the victory the Earth needed. As awesome as this moment was, it did raise a very important question: why didn't he gain this power the first time he died? Though the series answers that, it feels more like a contrivance to make Yusuke a demon for the next arc.

1 Rimuru Achieved His Demon Lord Form By Fighting A Mob Of Helpless Soldiers (That Time I Got Reincarnated As A Slime)

rimuru tempest fist

Most modern isekai have overpowered protagonists, and while it's a great series, Reincarnated as a Slime isn’t an exception. Rimuru Tempest starts out as one of the strongest people in his world...though he’s still not powerful enough to help his city when he’s nowhere near it. After the Jura Tempest Federation suffers major losses, Rimuru decided to do everything in his power to become a demon lord in the hopes of bringing them back to life. But to gain this major power-up, he didn't have to work for it at all. He wiped out an army that was so worthless most of them just stood there as they died from a single spell.

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