By definition, underdogs are at a huge disadvantage against their opponents. Whether less experienced or simply weaker, they are unlikely to succeed and easy for audiences to root for. One of anime's most popular conventions is when the underdog upsets expectations by winning in essential fights.

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Such victories have massive ramifications for their respective series, often resulting in the character in question being viewed in a more favorable light afterward. There are many instances throughout anime where an underdog has prevailed, showing how one should never give up simply because the odds are against them.

10 Team Seven Overcame Kaguya (Naruto)

Team 7 triumphs against Kaguya Otsutsuki.

Kaguya had every conceivable edge over Team Seven. In addition to being the progenitor of all chakra, her enemies were already exhausted from fighting the Fourth Shinobi War. Nonetheless, Team Seven managed to defeat her due to several extraordinary circumstances.

Not only were Sasuke and Naruto conveniently the only people capable of sealing her away, Obito sacrificed his life so that they could complete their mission. Should he not have had such a profound change of heart in such a short time, a dark shadow would be cast over the ninja world.

9 Baki Defeated Oliva, The Strongest Man In America (Baki)

Baki fighting Biscuit Oliva

Biscuit Oliva was the strongest man in America and one of the few fighters to have Yujiro's respect. In order to become more powerful, Baki fought him in prison. Immediately, the young man's odds were against him. Not only had Oliva knocked Baki out before, but he also weighed much more and even controlled the security guards.

Although Baki prevailed over Biscuit, the battle was extremely close and pushed both men to their physical limit. It also challenged Oliva's credibility while elevating Baki's own. Yujiro heard of the fight and was immediately impressed.

8 Hisoka, Killua, & Gon Teamed Up Against Razor (Hunter X Hunter)

Razor Holding Dodgeball - Hunter X Hunter

Razor was a man of fantastic talents. In addition to being a world-class hunter personally rehabilitated by Ging himself, he also defined the terms of the game played against Hisoka, Gon, and Killua.

Dodgeball gave an huge advantage to users of enhancement Nen, especially since Razor could throw so hard that his enemies' heads exploded. Regardless, Killua helped Gon catch the ball and throw it back at its user. After being defeated, Razor acknowledged Gon's skills and wished him luck on his continued adventures in Greed Island.

7 All Might Was Exhausted When Fighting All For One (My Hero Academia)

All might vs all for one

Despite being the world's strongest hero, All Might was at a major disadvantage against All For One. Since he'd already been using his muscle form to arrest the League of Villains, his strength was at its limit shortly after the fight began.

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To make matters worse, All For One stockpiled strength Quirks that allowed him to contend with the hero in hand-to-hand combat. Nearby civilians also complicated matters and put All Might at unnecessary risk. Should he not have won the battle with a final, desperate punch, Japan would have plunged into darkness.

6 Ichigo Prepared To Defeat Aizen (Bleach)

bleach ichigo vs aizen

When last they fought, Aizen humiliated Ichigo badly. The fight was so one-sided that Ichigo's swing could be stopped by his opponent's single finger. Since then, Aizen has been made more powerful through the Hogyoku.

Luckily, Ichigo came prepared. By burning his spiritual pressure as physical force, he harnessed enough raw striking power in order to put Aizen down. Nothing in the Espada leader's arsenal could contain or subdue Ichigo in that brief moment of time, resulting in his legendary defeat.

5 Armin Used His Wits To Take Down Bertholdt (Attack On Titan)

The Colossal Titan burns Armin in Attack on Titan.

Bertholdt was easily the most deadly weapon in Marley's arsenal. His titan form was sixty meters tall and took out a large portion of Shiganshina by activation alone. However, Armin and Eren devised the perfect plan to defeat him.

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While the former pretended to make a futile lunge at his nape, the latter prepared for an ambush. By the time Bertholdt was finished incinerating Armin, he was too weak to stop Eren from slicing out his weak spot. Paradis acquired the Colossal and restored Armin to life.

4 DIO'S Stand Was Stronger Than Jotaro's (JoJo's Bizarre Adventure)

Jotaro versus dio

DIO had every possible edge over Jotaro. Not only could the World freeze time, but his vampire physiology also made what should've been paralyzing or lethal blows relatively minor flesh wounds. Additionally, DIO was better armed and had much more experience than his youthful counterpart.

Nonetheless, Jotaro prevailed after his allies identified the secret behind DIO's ability. In the end, the villain's overconfidence and cautiousness proved his downfall since he did not make full use of the duration that the World could stop time for.

3 Aang Fought Ozai During Sozin's Comet (Avatar)

Ozai vs aang

Sozin's Comet was a rare event that significantly increased firebending strength. Since Ozai was already extremely formidable, this rendered him powerful enough to torch entire countries on his own. Further, Aang's refusal to kill Ozai also put him at a disadvantage since it made him regulate the force he could use.

Regardless, he managed to overcome the blazing villain by harmonizing the elements against him and fully mastering the Avatar state. In the end, Ozai's bending was stripped from him, and he was imprisoned alongside the Fire Nation's worst criminals.

2 Kirito Fought Aincrad's Creator, Heathcliff (Sword Art Online)

Kirito vs Heathcliff in Sword Art Online.

As Aincrad's creator, Heathcliff was effectively a god in his own world. This was seen during his first duel with Kirito, where he slowed time in order to avoid what should've been fatal damage. After his true identity was revealed, Heathcliff agreed to fight Kirito fairly and without abusing his powers as a game master.

Nonetheless, his encyclopedic knowledge of the universe he built allowed him to overcome Kirito's otherwise impeccable offense. However, when Kirito sacrificed the last of his life to take Heathcliff down, he was freed from the game before the NerveGear could kill him.

1 Sasuke Realistically Shouldn't Have Beat Itachi (Naruto)

Naruto Sasuke and Itachi's final moments in Naruto.

At the time, Itachi was a superior shinobi to Sasuke in every way imaginable. His sharingan was far more developed, and his Susanoo provided a serious obstacle his little brother could not meaningfully overcome. However, there were several key factors playing into Itachi's defeat.

Not only was he deathly ill before the fight began, but he also had no intention of winning. Itachi's only goal since the Uchiha genocide was to ensure his brother would be strong enough, and in their final duel, he was satisfied with how far vengeance had driven Sasuke.

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