My Hero Academia Sets Up Izuku's Uncontrollable Quirk

My Hero Academia has made the reveal of one uncontrollable quirk inside of Izuku Midoriya, which could end up being the power that ultimately stops his villain rivals – at a cost that may be too great to pay. As the Final War Arc brings us to the climax of My Hero Academia, the few lingering mysteries are quickly falling away – and for those not good at math, the One For All superpower has revealed all but one of the quirk powers of Deku's nine predecessors... until now. The Second User's power is now coming into focus, and the Kohei Horikoshi makes no secret that it will be a game-changer. 

(WARNING: My Hero Academia Manga Chapter 349 SPOILERS Follow!) 

The heroes' epic battle plan to defeat the League of Villains' army got a major monkey wrench thrown in when Himiko Toga snatched Deku through a portal to the wrong battle site. Izuku now has major ground to make up, and in the scene, we get the young hero is trying to combine every applicable quirk power he has to make the journey faster. The Seventh User's (Nana Shimura) Float quirk and the Third User's Fa Jin speed burst are enough to give Izuku a Superman-style flight path across the ocean – but with every second of the battle being so pivotal, he's sacred it isn't enough. 

The spirit of the Second User appears to Izuku to calm his nerves – but he also calls out Deku for almost doing something stupid: using his MetaAbility, which the Second User explicitly refers to as a "last resort" option. 

As the Second User explains to Izuku: 

"As One For All grew in strength, so too did all of our meta abilities within it. As a result, mine evolved into a particularly unique power. It's not something that can be wielded the usual way, as I once did."

That warning comes with a picture that shows this mysterious meta ability of the Third User being locked behind a big metallic door with a dozen padlocks on it. Clearly, whatever this power is it's something that comes with as much risk as it does potential reward. 

If we had to guess, the Third User's power could be some kind of power-boosting quirk. However, given the context of the conversation, it seems that while this power may have once been a useful tool for the Second User's allies (during the dark age of All For One's supremacy), the years being housed inside of OFA may have "evolved" the power boost effect to the point where it boosts power so exponentially it also burns out the user. Basically, My Hero Academia's version of Goku's Kaio-ken. 

My Hero Academia's manga has new chapters free to read online.