Toshinori Yagi

All Might (オールマイト, Ōrumaito) is the No. 1 Hero and the "Symbol of Peace".

Appearance
In his hero form, All Might is a very tall and over-musculated man whose design resembles the American hero comics. His hair spikes on top of his head and his whole body has more shadows than a normal human being. However, in his true form, he is an overly-skinny man who spits a lot of blood out of his mouth and his clothes appear wider. Note that in both forms, his eyes are sunken in, but the difference is that you can see his eyes in his true form.

Personality
All-Might's hero persona derives much from American hero stereotypes, in which that they're colorful and have a lot of dramatic flair. Always sporting a giant smile, he usually shows off a bright, can-do attitude that borders on being obnoxious. All-Might also tends to be extremely friendly and amicable, due to his popularity and years in the spotlight. However, when All-Might reverts back to being sick and scrawny (as a result of a previous battle), he tends to be less energetic due to his constant blood-spitting. Additionally, tries not to draw much attention to himself while in his true form, always afraid that others might learn of his current state of health.

Two personality traits always persist, though, whether he's in hero-mode or normal-mode: his optimism and his oafish-ness. All-Might has always had faith and hope that someone would come along, worthy enough to bear the "One for All" quirk. The manga also depicts him as sometimes being outsmarted by his students, and even his fellow teacher, Shouta Aizawa has called him an idiot a few times.

Entrance Exam Arc
All Might first appears when Izuku is being attacked by a villain. He then uses Texas Smash on the villain, saving Izuku. All Might is glad to see that Izuku is all right. He then decides to leave, asking Izuku to continue to support him. However, he is forced to land after Izuku grabs on to his leg. After doing so, he tries to leave again, but Izuku questions him on whether he can become a hero without a Quirk. All Might reverts back to his true form, shocking Izuku. He then tells Izuku is proffessionals must always put their lives at stake to save the day and thus cannot openly say whether it is possible to be a hero without a Quirk as it may not be possible. All Might says that if Izuku cares about saving people, he can always go on to become a policeman, as in that way he can be responsible for putting the villains in jail (even though it is ridiculed). He tells Izuku that it isn't bad to dream, but warns him not to obscure the facts and then leaves. All Might then sees that he wasted time in talking with Izuku, causing the villain he defeated before to escape, saying to himself that he is pathetic. After seeing Izuku's bravery in trying to save Katsuki from the villain, All Might decides to step in and uses Detroit Smash to defeat the villain, saving both Izuku and Katsuki. All Might then appears before Izuku, saying to him that he thanks him and has a proposal for him. He tells Izuku that he was touched by Izuku's bravery for trying to save someone despite not having a Quirk and tells him that he too can become a Hero.

All Might tells Izuku that he is worthy to inherit his strength. He tells him that his Quirk can be passed down and that Izuku has been chosen by him to be the next one to inherit his Quirk. Izuku asks why he would give someone like him his Quirk, to which All Might responds that he has been searching for a successor for a long time and now has found someone that he doesn't mind giving his Quirk to, saying that he despite not having a Quirk, tried to save somebody and that he shined more than any of the other heroes. Thus, All Might's proposal is whether he wants to inherit the One For All Quirk from him or not. Izuku accepts All Might's proposal. All Might begins to train Izuku for the next 10 months, explaining to him that in order for him to inherit his Quirk, Izuku's body (vessel) must be strengthened to the point of being able to handle the Quirk's power. All Might trains Izuku at the Seaside Park, a place filled with trash and tells him that he will clean up all the trash as part of training his body to become stronger. After 10 months have passed, All Might tells Izuku that he is now a genuine vessel. He then decides to give Izuku his reward for working so hard for the past 10 months: the One For All Quirk, saying that he has earned it fair and square. All Might gives Izuku his reward (a piece of his hair) and tells him to eat it so that he can inherit his Quirk.

One week later, Izuku receives a letter that will determine whether he was accepted into Yuuei or not. Izuku opens the letter in his room and a screen with All Might on it appears. He apologises for not contacting Izuku earlier and informs him that he will be working as a teacher at Yuuei. All Might tells him that he did fine on the written test, but since he scored zero points during the practical test he has failed. However, All Might tells him that because he rescued someone during the practical test, he earned 60 points, meaning he has passed and therefore being accepeted into Yuuei, much to Izuku's joy and happiness.

Quirk Apprehension Test Arc
All Might is seen secretly inspecting Izuku's participation in the pitch trial of the Quirk Apprehension Test, impressed with Izuku's focus of the One For All Quirk at the tip of his finger and for his quick thinking of using the One For All Quirk in the shortest time possible at the last moment as a workaround for not being adjusted to the Quirk. All Might approaches him, calling him a liar and says that he once expelled an entire new class of first-graders last year. All Might knows that he kicks students out with zero chances, finding it weird that he didn't expel Izuku on the spot and concludes to him that even he felt Izuku's raw potential. However, Shouta replies that Izuku's are above the "zero" mark and that it all. He continues to say that he can kick anyone out whose chances drop below that mark at any time, then leaves. All Might then says that they will never get along. All Might then appears as the teacher of the foundational hero studies, saying that they will have a battle of trial for the period. He tells his students that Yuuei have prepared their Hero Costumes and says to them to get changed into their costumes for the battle trial.

Battle Trial Arc
All Might explains to his students that they will be separated into Heroes and Villains for the battle trial and it will be a two on two team battle. He explains that in the battle trial, the villains will guard a nuclear weapon they intend on deploying and the heroes must stop them. He goes on to further say that the heroes can win by capturing the villains or reach the nuclear bomb before time runs out and the villains can win by capturing the heroes or keeping the core away from the heroes before time runs out. All Might then decides that the teammates and pairs will be chosen by lottery. After the lottery, All Might draws from the boxes and says that the pairs that will do battle is the heroes: Izuku and Ochako versus the villains: Katsuki and Tenya. He explains that the villains will go in the building first, then after five minutes, the heroes will go in. He tells them to go all out as it is a practical exercise, although he says that he will stop the battle trial if things get out of hand. All Might is seen in the surveillance room, saying to himself that Izuku won't get any special treatment from him and will grade him as harshly as the rest. All Might tells Katsuki to stop after seeing what his Hero Costume can do to amplify his Quirk and becomes worried for Izuku after Katsuki initiates a huge explosion.

All Might then tells Katsuki that if he uses another huge explosion, he will end the battle trial and he will lose, reprimanding him for trying to destroy the building that protects their stronghold (the core) calling it foolish. Although he feels that he should stop the battle trial, he thinks that it would be better for Izuku and Katsuki to continue battling as it is necessary for the future that they envision themselves. After being asked to stop the battle trial, All Might is about to suspend it, but after hearing Izuku call out to Ochako, he stops. After Ochako touches the core, All Might announces that the Hero team wins.

All Might approaches Katsuki, telling him that its time for his critique. He tells Katsuki that it doesn't matter whether he won or lost, but that he takes one look back, reflect on his experience and move on with life. In the monitor room, All Might says that Tenya was the best during the battle trial. After being asked why, he questions his students as to why he chose Tenya. After Momo Yaoyorozu gives her answer, he gives a thumbs up to her for being absolutely correct. During the next battle trial, All Might is impressed by Shouto Todoroki for not getting him comrade caught in the attack and at the same weakened his opponents' positions as well as refrained from damaging the core. After everyone participates in the battle trial, he tells everyone that they did well and instructs them to change clothes and head back to class. Although he wanted to give Katsuki counselling for his self-confidence, he realises that his transformation is running out of time and head to the nurse's office.

He is reprimanded by Kango Kyouyu for indulging his disciple, Izuku, too much and he says that he has nothing in his defence. They talk quietly, with him saying that his Quirk is secretly known by a selected few (including her). Kango asks if it is important to be a "Natural Born Hero" or "The Symbol of Peace" to which he replies that without such a symbol, the society of superhumans would fall to evil. Kango then tells All Might to be a better guide to Izuku. All Might then appears before Katsuki, trying to counsel him on self-confidence, although he is told in response by Katsuki that he will surpass him as well, thus All Might decides to leave Katsuki alone, finding that teaching can be difficult.

Rescue Trial Arc
All Might is seen using Missouri Smash on Vihara Headgear, defeating him and saving the family in the process. He then realises that his Quirk is steadily dropping off, as the amount of time he can keep his Quirk activated has decreased. In a flashback, Izuku is seen speaking to All Might telling him that he revealed to Katsuki about the secret of the One For All Quirk. However, All Might isn't angry about it since Katsuki interpreted it as nonsense and tells Izuku to keep the secret to himself and no one else since if the villains knew about his secret, all of them would probably want to steal his Quirk. He then tells No. 13 that he won't be able to appear at the Ultimate Space and Jams due to him using his Quirk too much and then takes a nap. After his nap, All Might tries to contact, No. 13 and Shouta, but to no avail. He decides to go to the U.S.J, but Mr Principal arrives to have a discussion with him, being held up by Mr Principal's endless talking, seeing that he hasn't changed either.

Quirk
"One For All" - All Might's Quirk grants him super strength, greatly enhanced agility and the ability to fly.

Moves

 * Texas Smash (Move): All Might throws a right punch with enough force that the wind pressure sends anything made of liquid flying away. This move was first used to save Izuku Midoriya from an unknown enemy in Chapter 1.
 * Detroit Smash (Move): All Might preforms that same attack as Texas Smash except her down is with a downward punch instead of a straight punch, the punch is powerful enough to create a large shock way that cleared the weather. This move was first used to save Izuku Midoriya and Katsuki Bakugou from an unknown enemy in Chapter 1.
 * Missouri Smash (Move): All Might runs towards an enemy while keeping his hand flat and hit the enemy one the head while running past them. This move was first used against Vihara Headgear in Chapter 13.

Battles
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5 Years Before Story Begins

 * All Might vs. Super Venom Chainsaw: Lose

Entrance Exam Arc

 * Izuku Midoriya and All Might vs. Unknown Enemy: Win

Rescue Trial Arc
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 * Kamui Wood, Mount Lady & All Might vs. Vihara Headgear: Win

Izuku Midoriya
At their first meeting, All Might thought that Izuku was just a fan, but he started to acknowledge him when he jumped to save Katsuki from the Hedoro Villain. From that moment, he was touched by Izuku's bravery (despite not having a Quirk) and decided he would pass his powers to Izuku, feeling that he is the only one worthy enough to inherit his strength, and they started to share a feeling of mutual respect for each other.

Shouta Aizawa
Not much is know of their past, but because of their personalities, they don't get along.

Kango Kyouyu
Kango is one of All Might's friends that know about his condition and his Quirk.

Mr. Principal
Mr. Principal is another of the few people that knows of his condition and was the person that offer him a teacher position at Yuuei.

Trivia

 * He likes movies.
 * His signature moves are named after states and cities in America.