My Hero Academia’s Hero Killer Arc is the Key to Everything That Came After

The Hero Killer Stain arc of My Hero Academia saw some of the students fighting on their own for the first time against a deadly opponent, which sowed the seeds for a variety of future events in the series, to the point where this may be one of the most important arcs of all.

The arc ostensibly focuses on week-long internships for the students, but it soon becomes dominated by Iida’s quest for vengeance against the Hero Killer, who attacked and paralyzed his brother, the hero Ingenium. Stain is shown to be a true fanatic, devoted to wiping out heroes he believes to be unworthy of the title–and his high bar means that everyone short of All Might is a target. This arc also reveals some major secrets about One for All, as well as the existence of All for One, All Might’s fated nemesis.

Stain is a Fascinating Character Who’s Hard to Pin Down

As the villain of the arc, Stain obviously holds a place of major importance throughout these chapters/episodes. He was first teased during the Sports Festival arc, when he attacked Iida’s brother in an area known as Hosu City. Stain is said to have killed numerous heroes already, and left others, like Ingenium, unable to perform hero work. Stain stands out from Shigaraki by having a clear ideology that he adheres to; whereas Shigaraki seems to only delight in chaos at this stage, Stain believes that false heroes are corrupting their world and has dedicated himself to killing them.

This ideology makes Stain very interesting, because he does have something of a point. There are many unheroic pro heroes, like Endeavor, whose personal life would be more fitting of a villain, or those who use their hero status as a way of becoming a celebrity, like Mount Lady. Even the upstanding young Iida isn’t immune, as Stain calls him out on his desire for vengeance over protecting the life of the injured hero, Native. Unfortunately for any Iida fans out there, though, this is pretty much the peak of his relevance to the story.

Deku is able to prove Stain means what he says, too, as his selfless defense of Iida and Native earns Stain’s respect, to the point where Stain actually saves Deku from the rampaging Nomu. Stain’s ideology continues to come up and play a role in the story long after Stain is defeated, and Stain himself does eventually come back, though not until after the Paranormal Liberation War arc. Without him, the League would’ve continued to flounder as an aimless group, and all their actions that follow would’ve been impossible to pull off.

The Internships Offer Spotlights to Various Characters

Aside from Stain, the arc also focuses on the internships students are doing with pro heroes for a week. While not everyone gets focus, the story checks in with many, including Kirishima, Bakugo, Uraraka, Yaoyorozu, and Asui. The anime actually expands the internship element a bit, with an entirely original episode dedicated to Asui’s internship, which involved battling against drug smugglers at sea. It’s exactly the sort of thing that an anime adaptation should be expanding on, and the episode doesn’t come across as filler at all.

Most important, of course, is Deku’s internship with All Might’s old teacher, Gran Torino, who uses a Yoda-like personality to befuddle the aspiring young hero and force him to figure things out for himself. Gran Torino’s guidance proves to be essential, helping Deku to figure out how to use One for All throughout his whole body rather than concentrating it in one body part, his “Full Cowling” mode. It’s a major turning point for Deku, as he no longer has to break his own bones in order to attack.

The internships do also underscore the Stain story arc; Iida chooses his internship with Manual specifically to get to Hosu and look for Stain. Yaoyorozu’s internship with Uwabami seems to exist solely to prove that there really are heroes undeserving of the title, as Stain claims, since she shoots commercials and performs interviews all week without ever lifting a finger to help. Bakugo’s internship with Best Jeanist also ends up being very important to his character, as Best Jeanist attempts to set the boy on the right path.

The Hero Killer Arc Sets Up Everything that Comes After

Among the most important elements of this arc is the fact that All Might is prompted to reveal the truth of One for All to Deku (and the audience). This involves informing Midoriya about the existence of All for One, a terrible villain who All Might believed he had killed many years prior, and that One for All exists specifically to stand against All for One. Midoriya didn’t just inherit power; he inherited a responsibility to fight against All for One, in whatever form that may take.

All for One obviously ends up becoming a huge element of the story, the Palpatine to Shigaraki’s Vader. It’s only a mention, of course, but All for One’s voice has been heard at this point on a few occasions, speaking to Shigaraki and Kurogiri. All for One wouldn’t go on to appear for a while still, but the specter of this dangerous villain (who managed to seriously injure even All Might) immediately gives cause to fear for Deku’s safety.

Stain’s defeat and association with the League also begins a swell of anti-hero sentiment among the public, something which would only get worse over time as the villains successfully strike again and again. This leads to more crime and vigilantism, which creates the kind of chaos All for One thrives in. It’s also only thanks to Stain’s ideology that Shigaraki is able to recruit his staunchest allies like Dabi and Toga, and it’s hard to imagine the series without them. It also reveals there’s more than one Nomu, and the Nomu would go on to be some of the biggest threats in the series.

Overall, the Hero Killer Stain arc features some important training and character moments for Deku, reveals All for One’s existence, has some incredible fight scenes, and lays the groundwork for many story arcs that would soon come to define the series. The events of this arc remain relevant all the way to the manga’s final arc, making it one of the most essential to read/watch. Aside from its importance to the greater narrative, though, it’s just a fun arc to experience, and showcases exactly what would make My Hero Academia a monster hit.

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