The fifth season of My Hero Academia, also known as Hiroaka, will begin airing in April. Many new facts have been revealed about the previously shrouded Quirk, "One For All." This time, we'd like to introduce the story's keyword, "One For All," which the protagonist, Izuku Midoriya, inherited from All Might!
All Might's Quirk: One For All
One For All is the Quirk of All Might, who reigned as the strongest hero in the series for a long time. All Might's Quirk is a physical boosting ability. To put it bluntly, it's the ultimate muscle-brained Quirk with no practical applications, but its output is off the charts. His body is strengthened with such incredible output that he can even change the weather with just one punch. He is the strongest hero, so much so that his very existence is said to be a deterrent to crime, and he continues to reign as the "symbol of peace."
The Exhaustion of All Might, AKA Toshinori Yagi
Five years before the story begins, Toshinori Yagi, also known as "All Might," had long reigned as the strongest hero. However, in a battle with his nemesis, All For One, he sustained serious damage to his internal organs and respiratory system. The aftereffects severely limited his use of his powers, leaving him emaciated and sickly. All For One was supposed to have been defeated at the time, but he himself survived, albeit with severe aftereffects.
One For All: Passed Down from Yagi Toshinori to Midoriya Izuku
All Might's Quirk, arguably the ultimate muscle-brained one, is essentially the ability to "store power and transfer it to someone else." The ability, inherited from the original One For All user, has been passed down through the generations. Furthermore, it also possesses the property of becoming stronger with each successive inheritance, making it a Quirk that grows stronger with each successive inheritance. Like the Emperor in Romancing SaGa II, it is a Quirk that grows stronger across generations. One For All is then passed down from the eighth All Might to Izuku Midoriya.
One For All: Potentially Destructive
One For All is the accumulated will of those who have inherited it, and the power's strength is also the accumulated will of those who have inherited it. Therefore, it places an enormous burden on the body, and if a half-baked body tries to use 100% One For All, the body itself will be destroyed. Early on, Deku suffered serious injuries many times because of this. Now, by conserving his power, he is able to control One For All to a certain extent.
Teach Me, All Might
Izuku uses his power during the entrance exam for U.A. and, as expected, suffers serious injuries. This is because he tried to use his power with an immature body, and Izuku subsequently tries to resolve the issue by conserving his power. However, All Might must have known about this, but for some reason, he didn't tell him. Since it's a life-threatening condition, he could have explained the dangers and how to use it, but he didn't. Possible explanations include: if it doesn't hurt, he won't remember; or All Might inherited it while his body was already fully developed, so he didn't have to go through such an experience; or the power's strength was greater than expected due to the amount All Might inherited.
Is One For All's roots in All For One?!
One For All's roots lie in the original One For All heir, the younger brother of All For One, My Hero Academia's greatest enemy, culprit, and mastermind. During a chaotic era in which humanity began to manifest Quirks, All For One used his ability to "steal and share Quirks," stealing the Quirks of his enemies and granting them to those who desired them, reigning as a charismatic evil figure. While order was eventually restored to the people, it was none other than All For One's dominance over the underworld.
Taiga Drama "One For All"
All For One's younger brother stood up to this domination head-on. Quirkless and frail, All For One's brother, caring for his younger brother, forcefully bestowed upon him the "power-storing quirk." However, All For One originally possessed the "ability to bestow quirks." This quirk, meaningless on its own, blends with the aforementioned quirk to transform into the "ability to store power and entrust it to someone." This ability was his very own power. That power was passed down to successors, accumulating over the years until, during All Might's reign, he finally managed to defeat All For One.
"One For All" is the ability to control multiple Quirks!?
With the ninth successor, it was revealed that "One For All" is the ability to control multiple Quirks. This ability is the Quirk used by previous successors, making Izuku essentially a hero capable of controlling multiple Quirks. It's just like Romancing SaGa 2, after all. However, it still wasn't as easy as I expected, and when his Quirk first activated, it went out of control and he couldn't control it himself. It's unclear why this ability was activated in Izuku's time and not All Might's, but at the very least, it's not because All Might lacked the potential, but rather that the time for it to happen just happened to be Izuku's. At least, there are descriptions of this.
Over My Dead Body! The High-Risk "One For All"
We've learned a lot from Izuku's activation of the Quirks of past successors and the visions he saw of the successors. Originally, One For All's power was so powerful that it destroyed the user's body. However, with the exception of a few, the successors all shared a unique characteristic: they all, with the exception of All Might, were short-lived. While some heroes died mid-battle, it turns out that this wasn't the only reason for their short lifespans.
A Curse of Short Life?
It has been proven that, with the exception of All Might, the inheritors of One For All have extremely short lifespans. The fourth inheritor of All For One, Shionomori Hiei, was the second-longest-lived after All Might, but died at the young age of 40. Moreover, the cause of his death was old age. One For All is an extremely powerful Quirk, but when a Quirk-holder uses it, their body cannot withstand it, and the Quirk continues to drain their life. All Might and Izuku, who are Quirkless, unintentionally met this condition. One For All was a Quirk reserved for Quirkless individuals.
Introducing the currently known One For All successors!
First Successor
His name is unknown, but he is All For One's younger brother and the progenitor of One For All. His original Quirk was the power to transfer Quirks, but All For One bestowed upon him the power to store Quirks, which changed it to the power to store and transfer Quirks. This is easy to imagine the Quirk inheritance method in Romancing SaGa II.
Second Successor
Not yet introduced.
Third Successor
Not yet appeared.
Fourth Successor: Shionomori Toei
His Quirk is Crisis Perception. Although he inherited One For All, Shionomori Toei, the fourth successor, felt that All For One was too strong for him to defeat. He continued to hone his skills to give hope to the future. However, he passed away at the young age of 40.
Fifth Successor: Daigoro Mannawa (Lariat)
A muscular man with a shaved head and goggles. His Quirk is Black Whip. It manifests as a rampage during joint combat training. Shinso's brainwashing stops his rampage, and he later meets Izuku in the spiritual realm and offers him advice.
The Sixth Successor: Kemuri
A black-haired boy wearing a coat that covers his neck. His name is Kemuri. He seems to be a junior of the Fifth Successor.
Seventh Successor: Nana Shimura
All Might's mentor and the grandmother of All For One's successor, Tenku Shimura. A bright, carefree woman with a constant smile, she lost her life in a battle with All For One and passed on her will to All Might. Her Quirk was Floatation. She was a person of great character and a model hero, but because of this, she kept her son away from dangerous environments, which would later lead to disastrous consequences.
The Eighth Successor: Yagi Toshinori (All Might)
He inherited One For All and rose to become known as the symbol of peace, a deterrent force in itself. He achieved his long-cherished dream of defeating All For One with that power, but was unable to deliver the final blow. However, both heroes suffered serious aftereffects from the battle, leaving the future to the next generation. He is Quirkless.
The Ninth Successor: Izuku Midoriya (Deku)
The protagonist of My Hero Academia. A boy who strongly admired heroes like All Might and Katsuki Bakugo, but was unable to even get to the starting line due to his lack of a Quirk. However, All Might discovered his courage to face powerful foes despite his Quirklessness, and All Might, exhausted from the previous battle, was searching for a successor, so he became the successor to One For All.
[My Hero Academia] One For All Summary
One For All, the quirk of My Hero Academia's protagonist Deku, has always been shrouded in mystery, but recently its mysteries have been gradually unraveled! While it still remains a mysterious keyword, it's sure to play a role in the story going forward, so we're excited to see it!
