My Hero Academia usually plays off conventional costumed tropes such as dashing protagonists and conniving villains. This allows for a familiar story uniquely placed in an academic environment. However, there are many characters who are better suited for a horror anime rather than a relatively upbeat shonen.

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Their abilities and appearance are so morbid that it almost seems inappropriate in context to the rest of the series. By identifying these dreadful harbingers and the true extent of their horrifying abilities, it becomes easier to appreciate the narrative's dark deigns.

10 Kuroiro Is Class 1-B'S Macabre Wraith

shihai kuroiro class 1b my hero

Kuroiro isn't the strongest student in Class 1-B, but he's easily the most perturbing. Using his Quirk, he can disappear into any shadowy surface and re-emerge just as easily. As a result, Kuroiro is superb for launching surprise attacks and creating openings that his teammates could exploit.

Luckily, Kuroiro is a student at U.A, so it's unlikely that he'll misuse his formidable power for the sake of evil. Nonetheless, his Quirk has incredible potential in battle and as a way to collect information.

9 Gang Orca Is Japan's Most Villainous Pro Hero

Gang Orca during the licensing exam in My Hero Academia.

Gang Orca was hand chosen to proctor the Hero Licensing Exam due to his villainous appearance and behavior. Out of all Japan's pros, his monstrous appearance resembles a genuine threat that the students might one day face the most.

During the exam, Orca proved every bit as powerful as his frightening appearance suggests. He obliterated Todoroki's massive icebergs using sonic vibrations and contended physically with incredibly powerful heroes. It comes as little surprise that Orca is rated highly among Japan's finest heroes even if he seldom takes to field work directly.

8 Gigantomachia Is An Unstoppable Brute

Gigantomachia in My Hero Academia.

Gigantomachia's presence is unlike anything else in the series. As towering as he is sinister, the villain forced Gran Torino's retreat seconds after making his official debut. This was particularly impressive considering that Torino is a veteran hero who once fought alongside Toshinori and even Nana Shimura.

Unlike Mt. Lady, Gigantomachia has more than size to make him frightening. His skin is extremely durable, and he can fight for roughly a month without tiring. When breaching Re-Destro's fortifications, not even the combined power of the Meta Liberation Army was capable of slowing the monster down.

7 Seiji Mutilated Enemies Beyond Recognition

Seiji turns people into Meatballs in My Hero Academia.

Seiji himself may not have been intimidating. He was condescending and snobby, resembling an upper class aristocrat far more than a common villain. However, the student's "Meatball" Quirk was arguably the most horrifying thing Class 1-A encountered at the time. Some heroes like Bakugo even had the misfortune of falling victim to it firsthand.

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When trapping an enemy in one of his sludge-like appendages, Seiji can sculpt them into grotesque piles of meat. They are completely helpless and at his mercy in this state. Fortunately, they're capable of reverting to their original forms.

6 Overhaul's Quirk Had Dastardly Potential

Overhaul from My Hero Academia.

Like Seiji, Overhaul wasn't physically intimidating. However, his Quirk had a vast number of terrifying applications that make him among the series' most chilling villains. Overhaul only needs to touch his opponent once to reduce them to a bloody mist.

As a result, he's nearly unbeatable in melee combat. When backed in a corner, he can also forcibly splice other peoples' bodies into his own, stealing their Quirks and muscle mass to become a nightmarish aberration of immense proportions. Were it not for Eri's assistance, no hero would have been able to prevent his escape.

5 High-End Pushes The Limits Of Modern Technology

High-end nomu

High-End was one of the most powerful nomu to date. Designed to track down and kill professional heroes, his battle with Endeavor nearly cost unprecedented casualties. Between his fiendish appearance and endlessly rejuvenating body, he was a creature with almost no weaknesses.

In the end, Endeavor had to incinerate High-End on a molecular level in order to put him down for good. However, the battle proved so strenuous that he was permanently scarred in the process. The slash across Endeavor's face embodies his attempts to atone for previous sins.

4 All For One Is Menacing Under The Right Conditions

All For One In My Hero Academia

All For One has many factors that qualify him as the most terrifying being alive. He can steal Quirks, has lived far longer than any person should reasonably be able to, and is responsible for almost every atrocity in the series directly or otherwise.

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Still, he has his limitations. In addition to deliberately trying to make himself as approachable as possible, beneath All For One's helmet is a blind man whose body has been broken beyond repair. This makes him somewhat dependent on his colleagues in order to fulfill his machinations.

3 Kurogiri's Body Is A Mystifying Enigma

Kurogiri in My Hero Academia.

Although among the League's most mild-mannered members, one would be wise to fear Kurogiri. His abyssal body makes it impossible to discern facials features – creating an overall aesthetic of a remorseless, imperceptible villain.

Further, Kurogiri can rapidly expand himself to swallow victims or teleport comrades to and from harm's way. This means that he is fully capable of ambushing heroes in an instant, capturing them well before reinforcements arrive.

2 Shigaraki's Decay Has Only Become Stronger

Shigaraki Tomura grinning while staring downward in My Hero Academia.

Tomura Shigaraki's "Decay" Quirk has always been horrifying. Its ability to reduce targets to ash makes him an unprecedented danger on the battlefield. Now that it has been evolved beyond its original capacity, he can endanger multiple threats at once without needing to make direct contact.

Considering that Shigaraki has matured from a brooding teenager into a diabolical adult, he is much more difficult to defeat. With the full might of the Meta Liberation Army under his command, Shigaraki's growing influence and rapidly evolving body make him impossible to predict.

1 Moonfish Was The Most Terrifying Villain Ever Designed

Moonfish from mha

Moonfish may be far from the strongest villain in the series, but he's easily the most perturbing. His character design alone should tell viewers what they need to know about him, having never managed to escape the confines of his straight jacket.

Unlike Shigaraki, Moonfish isn't much for words or reason. He simply seeks to kill as many victims as possible, proven through the terror he spread during the Forest Camp arc. Should Tokoyami not have employed his own formidable Quirk when defeating him, Moonfish wouldn't have had a problem slicing up U.A's weaker heroes.

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