Long ago, a man with a Quirk that could steal other Quirks and give them away forcibly gave his seemingly Quirkless younger brother a Quirk that allowed him to stockpile power within his body. However, unknown to either of them, the younger brother already had a Quirk with no other power than that it could be transferred to another person. The transferance Quirk and the power stockpiling Quirk merged into one and from then on became One For All. The younger brother somehow discovered this. He had a strong sense of justice and he tried to defeat All For One, but given the huge difference in their strength, the younger brother failed.
The younger brother decided to entrust the Quirk to future generations of Heroes, hoping that they would cultivate One For All and one day put a stop to All For One. Very few knew the truth about One For All, for fear of what Villains would do if they found out that the world's most powerful Quirk could be transferred.
All For One sought after One For All and as a result, almost all of the users of One For All were killed by his hand, but not before they each had the chance to pass on the Quirk to a successor so that it could reach the future.
The seventh user, Nana Shimura, was the last holder killed by his hand, while her apprentice and heir to One For All, All Might, fought All For One at least twice, winning both battles. The Quirk was passed down through nine generations, growing stronger with the passage of time. Currently, One For All is one of the most powerful Quirks in existence, albeit being very difficult to fully master.
One For All is a transferable Quirk that can be passed on from one user to the next. It's name comes from its nature; being 'one' Quirk for 'all' people. In order for the Quirk to be transferred, the recipient must ingest a sample of the predecessor's DNA (ex. a strand of hair or a drop of blood).
In order for the Quirk to be transferred, the current owner must freely choose to transfer it. Because of this, the power cannot be forcibly taken, however, it can be forcibly given, as the recipient doesn't have to agree to anything. Since One For All can't be forcibly taken, it is the only Quirk that can be used in combat against All For One, as any user of All For One would simply be able to steal any other Quirk.
One For All also allows the user to stockpile an enormous amount of raw power, allowing them to significantly enhance all of their physical abilities to a superhuman level. This results in unbelievable levels of strength, speed, agility, and durability.
The user can focus the stockpiled power into a single body part, or spread the power evenly throughout their body, although, focusing the power puts greater strain on the part of the body where the power is focused. The user is also able to control the percentage of the power that they activate.
One For All can even grant the user an exceptional strength boost to their given Quirk, if they have one.
The core of One For All has grown in strength from being passed from user to user, and the Quirk Factors of all of the previous users have merged into the core, granting the current user the ability to access these Quirks. The Quirks have significantly increased in strength since they were used by their original users; this is due to the nature of One For All's core stockpiling power and increasing in strength from user to user.
In addition to the Quirk Factors merging with the core, One For All carries echoes of the consciousnesses of all of the previous users.
One For All draws power from the cries of help of those in need, as they are like a direct order to the user.
One For All also seems to alter the user's appearance in different ways. For All Might, it significantly enlarges his muscles and overall body mass to make him look like a completely different person, similar to a giant. For Izuku, usage of One For All causes the empowered part of his body to glow, with vein-like lines crossing through each other. His body also generates crackling, green energy that resembles lightning bolts when he activates One For All: Full Cowling. It is unknown what the usage appearance of One For All looked like for its previous handlers, however.
One For All can be duplicated, but since it is an accumulation-type Quirk, the amount of power given is practically insignificant; shown when Neito Monoma did not gain any substantial increase in power after copying it.
When One For All is transferred, the new user's body is not naturally suited to it as they would be with a Quirk they were born with (ex. Someone who breathes fire doesn't burn their mouth while using their ability). In addition, One For All is a lot to handle; if ones' body can't handle the power, then their body could be blown apart. Because of this, the successor must undergo intense and rigorous training of the body.
After One For All is transferred, the previous user is left with only residual power of the Quirk (or "leftover embers"). While they would still be able to utilize the power to essentially the same degree as before, continuous usage of it will cause a strain on the user before ultimately, the wielder cannot make a tangible use of the Quirk at all. After All Might's final battle against All For One, his ability to sustain his Muscular Form was reduced to seconds, rending him unable to make any use of his residual power.
The Quirk factors of each of the previous users have merged with the core of One For All and have since increased in strength due to One For All's nature of stockpiling power. Izuku is the first user capable of accessing the Quirks of the previous users.
The Quirks within One For All are:
- Blackwhip: The Quirk wielded by the fifth user, Daigoro Banjo. This Quirk allows the user to create tendrils of dark energy from their arms. These tendrils are good for grappling and increasing the user's mobility.
- Float: The Quirk wielded by the seventh user, Nana Shimura. This Quirk allows the user to levitate.
- Four Unknown Quirks: Four unknown Quirks that originally belonged to the 2nd, 3rd, 4th, and 6th users of One For All.
Known Users and Usages
One For All has been bestowed to nine different hosts in total, starting with All For One's younger brother. Alongside the Quirk, its origins and the story between the two brothers have been passed on.
Because One For All can only be transferred willingly, it's presumed that each wielder had some form of personal connection with at least their corresponding predecessor and successor. Every host was entrusted, not only with the Quirk, but also with the duty of using it to stop the evil of All For One.
All of the previous users of One For All seem to be aware of Izuku being the ninth holder of the Quirk. When All Might was researching the previous users of One for All, he was unable to find any information on the second and third users due to the multi-faceted nature of One for All and the era back then.
All For One's Younger Brother
The first user of One For All.
He was the younger brother of the powerful Villain, All For One. He was initially believed to not have a Quirk, but in reality, he had a Quirk with no other power than that it could be transfered to another person. One For All was formed from the fusion of his given Quirk and the power stockpiling Quirk All For One had forced upon him.
Though small and sickly, he had a strong sense of justice and did not back down from opposing his brother's evil deeds. The younger brother attempted to defeat his older brother with his newly-merged Quirk, but didn't have the sufficient power to do so.
He then passed One For All down to an unknown successor, in the hopes that someone in the future would eventually stop his evil older brother once and for all, a cycle that continued to the present day. Even after his death, the brother is aware of Izuku being the ninth wielder of One For All and showed him the events leading to the creation of the Quirk.
The second user of One For All.
Nothing is currently known about this person.
Their proficiency with One For All is unknown, as is their given Quirk.
The third user of One For All.
Nothing is currently known about this person.
Their proficiency with One For All is unknown, as is their given Quirk.
The fourth user of One For All.
Almost nothing is known about this person, but they appear to have two scars or markings on their left eye, going from around his right Supraorbital ridge to his left lower lip. He also seems to have light-colored hair.
Their proficiency with One For All is unknown, as is their given Quirk.
The fifth user of One For All.
Described as being "super funky".
His proficiency with One For All is unknown, though he likely used it in conjunction with his given Quirk, Blackwhip.
The Sixth user of One For All.
Next to nothing is known about the person who had One For All before Nana Shimura. The only thing known for sure is that the user was a man with dark hair who wore a high collared jacket.
His proficiency with One For All is unknown, as is his given Quirk.
The seventh user of One For All.
Nana was a very compassionate and noble individual. She is regarded as having been a truly great and exceptional Hero by incredibly powerful Heroes, such as All Might and Gran Torino.
Little is known about Nana's proficiency with One For All, other than she was not capable of bringing down All For One. She likely used One For All in conjunction with her given Quirk, Float.
The eighth user of One For All, and the first user who was born Quirkless.
Throughout his career, Toshinori was regarded as the most powerful hero of all time and remained undefeated. With the goal of being a pillar for society, he put One For All to great use, defeating all sorts of criminals, rescuing countless people from danger, and turning himself into a legend.
Toshinori, better known as the Pro Hero, All Might, is probably the best-known user of the Quirk, if not one of the most talented. Gran Torino once stated that Toshinori did not take long to adapt to One For All, having been blessed with an extremely resilient body, despite being born Quirkless. He was able to control and focus his power into any extremity he chose without recoil.
However, due to an untreatable wound that was inflicted on him by All For One in their first known encounter, he could only utilize his Quirk for three hours a day; any more and it would strain his body. Even if he was forced to employ One For All too much, the time limit for using his Quirk would shorten as a repercussion.
During his second battle with All For One during the League of Villains' hideout raid, Toshinori completely depleted all the "remaining embers" of One For All from his body in order to defeat the villain, essentially leaving him Quirkless once again. Although he can still transform for an instant, he cannot maintain his muscle form anymore as it causes great strain on his body, reverting back very quickly. Having retired himself from heroic activity thanks to this, Toshinori now dedicates himself to solely assisting Izuku in mastering the power of One For All so that he may become a great hero of his own.
He gave Izuku Midoriya One For All by giving him a strand of his hair.
The ninth user of One For All, and the second user who was born Quirkless.
Initially, Izuku had very little control over the Quirk and could only use One For All at 100 percent power. While this allowed him to unleash incredibly powerful displays of strength, it came at the cost of gravely injuring his own body. This is because the training Izuku did prior to receiving the Quirk was only the bare minimum needed for using One For All without his limbs being blown off.
Later, Izuku found a way to minimize the damage to himself by focusing One For All's power into just his fingers. While he still ended up breaking his fingers, he was able to strike powerful blows and generate strong air currents.
Izuku likened the power to an egg exploding in a microwave; so to help him control the Quirk, he pictured the egg not exploding. During the U.A. Sports Festival, Toshinori estimated that Izuku could handle 5 percent of One For All full power without hurting himself.
During his internship with Gran Torino, Izuku was told by the elder Hero that his movements and smashes were too slow, as he treated One For All more like a special move rather than a natural ability. While training himself, Izuku tried regulating the Quirk's power back and forth into his legs and arms in order to scale the side of a building. Unfortunately, he discovered that Gran Torino's previous evaluation was correct and failed to do so.
Izuku eventually realized that he was using One For All solely in the limbs that required it, thus severely slowing down his overall reaction time. To compensate, Izuku developed One For All: Full Cowl, which takes advantage of the five percent that Izuku can safely work with to increase his strength and agility by letting this small amount of One For All to flow throughout his whole body.
Using Full Cowl, Izuku can easily scale the side of buildings, jump large clearings between structures, and quickly navigate through cluttered areas. Many of his newfound movements are attributed to watching the way Katsuki Bakugo propels himself using his Explosion Quirk. Izuku could react to the speed of Gran Torino and even held his own against Stain in his first real fight. Even so, if Izuku does not remain calm and alert while using his Quirk, he might go over his five percent limit and injure himself.
By the time of his second fight with Katsuki, thanks to all the training he had done, Izuku instinctively found out how to wield One For All at 8 percent of its full power without repercussions.
During his battle with Overhaul, Izuku discovered that he could use 20 percent of his full power for a very short time, if the situation was desperate enough. However, extended usage would cause him to damage himself. While in physical contact with Eri, Izuku was temporarily able to use One For All at 100 percent of its full power with no consequences, due to Eri's reversing Quirk constantly rewinding all of the damage Izuku was doing to his own body.
Around the time of U.A.'s School Festival, Izuku, lamenting his "inability" to perform any long-ranged moves in the battle against Overhaul, was told by All Might that he already had the capacity to do so. All Might had planned to wait until his disciple had control of at least 15 percent of One For All to begin teaching him said moves, but seeing that Izuku had learned how to briefly bring out 20 percent of One For All, which was more than enough to manipulate wind pressure, All Might decided to instruct him on how to perform them. After learning the new technique and receiving new equipment from Mei Hatsume to help harness the wind created, Izuku was able to put the super move to the test in his battle against Gentle Criminal.
During the fifth round of the joint training session between Class 1-A and 1-B, dark energy tendrils started to shoot from Izuku's arm that heavily damages his surroundings and pulls him along against his will. This causes him intense pain and he can't deactivate One For All in this state. With the efforts of Ochaco and Hitoshi, they were able to stop the rampage of One For All by brainwashing Izuku, but this sent Izuku's mind into his subconscious, where he meets Daigoro Banjo the fifth wielder of One For All. Daigoro explains that the Quirk factors of previous holders have merged with the core of One For All and have increased in strength since the eras of the original holders of the Quirks, due to One For All's nature stockpiling power. Daigoro tells Izuku that there are five other Quirks that he will manifest and that the Quirk that he had when he was alive, the same Quirk that created the dark tendrils, is called Blackwhip.
After awakening from the dark world within himself and resuming the match, Izuku was able to consciously activate Blackwhip and control it. By controlling his own emotions and by looking back at his memories of when he first began training with All Might for emotional support, Izuku was able to briefly activate and use Blackwhip with his own will, but quickly deactivated it due to the pain from his body not being strong enough to handle the enhanced Quirk, and decided that he won't be ready to use it until he fully masters One For All in the future.
After training with Blackwhip for a while, Izuku manages to bring it out to save cars from being destroyed, showing proficiency with the Quirk. Izuku also manages to increase his limit of One For All from 8 percent to 15 percent.
Despite the period of transfer and possession being extremely brief, Katsuki demonstrated great proficiency with the Quirk. He was able to instantly use One For All: Full Cowl - 100% without any prior instruction, and his body was able to handle the sheer power of One For All without being blown apart. However, this was likely due to being exposed to Katsuma Shimano's Cell Activation Quirk, which enhances the body's physical performance.
When Katuski used One For All to enhance his given Quirk, Explosion, it became so powerful, standard blasts from it could create enormous craters. The temperature of the explosions was also greatly increased, to the point where it could melt through solid rock in a similar manner to lava as Katsuki came into close proximity to it.
At the end of his and Izuku's fight against Nine, Katsuki lost One for All, and the Quirk remained in Izuku's body. Toshinori initially suspected that the Quirk stayed with Izuku because Katsuki lost consciousness prior to the transfer's completion, but later theorized that One For All kept itself inside of Izuku due to his willingness to protect others, even if it meant losing the power.
Izuku gave Katsuki One For All by swapping blood through the open wounds on their hands.
Named Super Moves
All Might's Super Moves
- California Smash (カリフォルニア スマッシュ Kariforunia Sumasshu?): All Might's attack with a frontal somersault leading into a downward punch. This move was first used against a villain while he was studying abroad in the United States.
- Carolina Smash (カロライナスマッシュ Karoraina Sumasshu?): All Might runs towards an enemy while keeping his hands in a cross position, then in a downwards cross chop to the enemy's head. This move is first used against Tomura Shigaraki, but it is intercepted by Nomu, who withstood the full force of the attack, seemingly unharmed.
- Detroit Smash (デトロイトスマッシュ Detoroito Sumasshu?): All Might performs that same attack as Texas Smash except this move is with a downward punch instead of a straight punch. The punch is powerful enough to create a shock wave large and powerful enough to clear the weather. This move is first used to save Izuku and Katsuki Bakugo from the Sludge Villain.
- Double Detroit Smash (ダブルデトロイトスマッシュ Daburu Detoroito Sumasshu?): All Might and Izuku use One For All at 100% and combine their Detroit Smash attacks to create a smash more powerful than anything they can accomplish alone. It was first used in the movie "My Hero Academia: Two Heroes" to defeat Wolfram, the main antagonist of the film.
- Missouri Smash (ミズーリースマッシュ Mizūrī Sumasshu?): All Might runs towards an enemy while keeping his hand flat and hits the enemy on the head while running past them. This move is first used against Trapezius Head Gear.
- Nebraska Smash (ネブラスカスマッシュ Neburasuka Sumasshu?): While throwing a punch, All Might rotates his arm to create a tornado. This move is first used to destroy a swarm of two hundred Mini-Bombers.
- New Hampshire Smash (ニューハンプシャースマッシュ Nyūhanpushā Sumasshu?): All Might blasts himself towards his enemy and smashes his body into the enemy, crushing and injuring the enemy with his great weight. This move is first used to propel himself at Izuku.
- Oklahoma Smash (オクラホマスマッシュ Okurahoma Sumasshu?): All Might whirls around while enemies have latched onto him, spinning with enough force that when they are released they are easily thrown through concrete. This move is first used against Nomu however it was named during the Kamino ward incident.
- Texas Smash (テキサススマッシュ Tekisasu Sumasshu?): All Might throws a right punch with enough force that the wind pressure sends most things flying away. This move is first used to save Izuku from the Sludge Villain.
- United States of Smash (ユナイテッドステーテスオヴスマッシュ Yunaiteddo Sutētesu Ovu Sumasshu?): All Might's final and strongest move. Using the last remnants of One For All left in him, All Might delivers a massive punch with enough force to reverberate shockwaves. This unstoppable attack was used to defeat All For One and marked the end of his hero career.
Izuku Midoriya's Super Moves
- Detroit Smash (デトロイトスマッシュ Detoroito Sumasshu?): The same as All Might's move, except Izuku sometimes does it in the form of an uppercut, creating an air pressure blast.
- Delaware Smash (デラウェアスマッシュ Derawea Sumasshu?): Izuku flicks his finger to create a powerful shock wave. Doing this fractures said finger, limiting the number of times he can use this move without gravely injuring himself to 10 times.
- One For All: Full Cowl (ワン・フォー・オール フルカウル Wan Fō Ōru Furu Kauru?, Viz name: "One For All: Full Cowling"): This technique allows Izuku to activate 5%, and later 8%, and then 10-15% of One For All throughout his body, letting the power course and flow through him instead of concentrating it in one location and negating the need to "turn on" the power every time he needs to use it. Activating this technique gives him enhanced strength, speed, mobility and agility. It also prevents him from breaking his bones when attacking.
- 5% Detroit Smash (5 パーセント デトロイトスマッシュ 5 Pāsento Detoroito Sumasshu?): Izuku activates One For All: Full Cowl, then jumps into the air and delivers an enhanced downward punch to the opponent. He has also used this move in the formof a straightforward punch.
- Delaware Smash Air Force (デラウェアスマッシュエアフォース Derawea Sumasshu Eafōsu?): Izuku uses his upgraded gloves to direct a blast of compressed air against his foe, possessing enough concussive force to stun Gentle while he was in mid-air, giving Izuku an opening to catch up to him. By using all five of his fingers, he can launch up to four Delaware Smashes simultaneously.
- One For All: Full Cowl - Shoot Style (ワンフォーオールフルカウル シュートスタイル Wan Fō Ōru Furu Kauru Shūto Sutairu?): A fighting style of using One For All that deviates from All Might. Izuku realizing that just imitating All Might's style which has its special moves centered on his fists was not the best style for him and was actually causing more harm to his arms, he developed a new style that centers more on his legs with the help of his friends. Shoot Style concentrates One For All: Full Cowl's effects in his torso and legs rather than his arms, allowing him to put out even more power due to the fact that the human leg muscles are naturally stronger than the human arm muscles, granting him more power and stability.
- Shoot Style: St. Louis Smash (シュートスタイルセントルイススマッシュ Shūto Sutairu Sento Ruisu Sumasshu?): While using the Shoot Style, Izuku leaps into the air and before swinging around to deliver a roundhouse kick to the opponent's face. Izuku used this move to incapacitate Gentle Criminal, who had been empowered by La Brava's Lover Mode Quirk to match Izuku's use of One For All: Full Cowl at 8% of its power.
- One For All: Full Cowl - 100% (ワン・フォー・オール フルカウル 100
%Wan Fō Ōru Furu Kauru 100 Pāsento?): Izuku activates One For All to its fullest extent throughout in Full Cowl, granting him a tremendous boost in speed and strength that allowed him to easily overwhelm the likes of Chisaki. This is first used against Kai Chisaki to protect Eri. The power increase seemingly gives him fire-like trails coming from his eyes and light colored hair. He can only use it infinitely with no damage done to his body while in physical contact with Eri because her Quirk constantly rewinds his body to a previous state.
- One For All 20%: A technique that allows Izuku to use 20% of One For All throughout his body, it causes a lot of pain to the point that he feels as if his bones are about to break.
- One For All 30%: A technique that allows Izuku to use 30% of One For All throughout his right forearm. It was used in conjunction with Melissa Shield's Full Gauntlet, nullifying any normal drawbacks to using One For All at higher percentages. It is unknown how this percentage affects Izuku's body under normal conditions.
- One For All 100%: A technique that allows Izuku to attack using the full power of One For All in one concentrated part of his body. After initial use, the limb breaks instantly. He can still use expended limbs in combat, but it causes scarring once they're completely healed.
- 100% Detroit Smash (100 パーセント デトロイトスマッシュ 100 Pāsento Detoroito Sumasshu?): While using 100% of One For All, Izuku strikes his target with a lunging punch.
- 1,000,000% Delaware Detroit Smash (1000000 パーセント デラウェアデトロイトスマッシュ 1000000 Pāsento Derawea Detoroito Sumasshu?): Izuku activates 100% of One For All during an adrenaline rush and then strikes his opponent by first using a Delaware Smash and then a powerful Detroit Smash, hence the Delaware Detroit Smash. During the climax of his battle with Muscular, Izuku manages not only to overpower but also to launch his augmented opponent with enough force to create an impact crater in solid rock with the strike alone.
- To date, most of the moves using One For All are named after states and cities in the USA (e.g. Missouri Smash, Delaware Smash). This is consistent with the manga artist's desire to model All Might after American comic book heroes, especially in All Might's hero form (Captain America and Superman). It is unknown if, like Izuku, the naming theme is passed from teacher to student, or if this unique to All Might with Izuku's admiration carrying over.
- According to All Might, to activate One For All, the user must clench their buttocks and scream "SMASH!" within their heart.
- So far every named user has had a number in their name somehow correlating to what number user they are.
- Daigoro Banjo has a kanji in his given name that's homophonous to 5.
- The 7th user is Nana Shimura, with her given name being a homophone to 7 in Japanese.
- Toshinori Yagi has the kanji for 8 in his surname.
- One of the kanji in Izuku's given name is homophonous to 9.
- One For All's name is an inversion of All For One, showing the differing philosophies between their wielders. One For All showing "One Quirk for All people" (through passing it on from person to person) and All For One showing "All Quirks for One person" (through taking Quirks from others).
- Users of One For All manifest differently to the point where it defies regular classification. All Might transforms into a musclebound giant, which correlates to the Transformation Class. Deku's veins glow red could easily place him in the Emitter Class because the power of One For All starts coursing through his veins. Currently, it is unknown if the past and future users will manifest One For All and how it will be properly classed.
- It is unknown if One For All can be passed back to a previous user if the current user allows it.
- As the truth behind One For All is only known to a select few, Izuku's Quirk is listed as "Super-Power" in U.A. and other records.
- Toshinori still has a few side effects left over from One For All such as, if he attempts to activate his (former) Quirk, he still goes in muscle form for a short period of time.
- According to Gran Torino and Toshinori, using One For All at 100% took far less time for Toshinori than most users, and even Izuku.
- Izuku states that One For All is "one of the seven great mysteries of the world". The other six "great mysteries" are unknown.