My Hero Academia finally reveals Shigaraki's original Quirk (and it's not Decay)

My Hero Academia manga concluded in the second half of 2024, ending in a way that satisfied most readers of the series. While the story wrapped up many of its major elements effectively, a few characters and their relationships didn’t receive the kind of closure fans expected.

When this topic comes up, fans often wonder about Midoriya and Uraraka’s romantic relationship. However, this time the discussion centers around Shigaraki Tomura, one of the story's main antagonists. The release of new content via the My Hero Academia Ultra Age got fans talking about Shigaraki and his Quirk. Based on what has been shown in the book, it’s clear that Decay wasn’t his original Quirk, and fans might have an idea about what it originally was.

Disclaimer: This article might contain spoilers from the manga chapters.

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Shigaraki’s unnamed Quirk might have been revealed as per My Hero Academia Ultra Age

Before we dive into the topic, it’s important to understand what the Ultra series is. This is an installation of fan books that Kohei Horikoshi himself worked on. It has detailed information about various characters, their Quirks, and much more. Fans have perused this book and seem to have found some new information about Shigaraki Tomura. Based on what was shown in the manga, it's clear that Decay was never his original Quirk.

It was All For One who managed to implant that Quirk into Shigaraki Tomura when he was a child. This was part of his plan, as he wanted a pawn for his own tyrannical goals. Shigaraki experienced extreme trauma since he ended up killing the people he loved because of his touch. Naturally, this led fans to wonder: What was Shigaraki Tomura’s original Quirk in the My Hero Academia series?

The answer appears to be an unnamed Quirk showcased by All For One during the final story arc of the manga series. He used a Quirk that provided him with a form of acceleration with the help of a solid, ring-like structure. The ring-like structure in question provided him with a boost in speed. This was rarely seen in the manga.

Some fans are still debating the canonicity of this information. There is one section of fans that believes that his decay was just a modified version of the Overhaul Quirk that missed the reconstruction aspect. This topic seems to be a topic of debate among fans, despite the series’ conclusion in 2024.

Furthermore, some fans tried connecting Tenko to Nana, and they believed that the Quirks should be similar. However, the information in the Ultra series seems to point towards the fact that the unnamed Quirk that gives its user a speed boost could have been Shigaraki’s original ability in My Hero Academia.

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Conclusion

While fans continue to debate this topic, any message from the original author should be treated as the absolute truth. Therefore, it’s quite likely that Shigaraki’s original Quirk in the manga was a ring-like structure that gave the user a speed boost during fights. However, fans would certainly appreciate further insights from Horikoshi once all books of the Ultra series are released.

Stay tuned for more My Hero Academia anime and manga news as 2025 progresses.

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