All For One

"You've failed again, Tomura. But you mustn't lose heart. There will be more chances to set things right. That's why I've brought along your little band. And the boy... because you determined that he is an important pawn. So go and try again. That's what I'm here to help you to do. It's... all... for you."

- All For One's last words to Tomura in All For A Certain One "All will be well now, for I am here."

- All For One's slogan.

All For One (オール・フォー・ワン Ōru Fō Wan), also known as Sensei (in Japanese: 先生 Sensei) is the central main antagonist of Boku no Hero Academia (My Hero Academia in English) Manga and Anime series. A man with a completely deformed face who was defeated by the hero, All Might, and founded the League of Villains with Tomura Shigaraki as his successor and the main force of the organization. After his defeat, Tomura has taken his place as the leader of the league.He was the main villain of the Hideout Raid arc.He is the archenemy of All Might.

Appearance
In the past, he appeared as a normal young man with a notable suit and short hair. However his face is not shown completely.

After his crushing defeat, he appears completely different than before. His face is heavily deformed with a scar on his neck and on his head, resulting his loss of eyesight. He also has two tubes connected to his throat which allows him to breath.

When battling the pro heroes and All Might, he wore a mask with a skull-like structure that acts as a life support system. Although it seems that he doesn't really need the mask, as the mask was heavily damaged in his second battle with All Might, yet he was still breathing normally.

Personality
All For One is shown to be a manipulative, mysterious, and sinister individual. He is able to create complex and elaborate plans in a little matter of time and then order Tomura to fulfil them.

He is also a calm individual, even in the worst situations. When he was defeated by All Might, not only did he show no sign of anger and frustration, but he was happy and assured himself that he won by destroying the meaning of "Symbol of Peace". He was also not angry nor disappointed with Tomura's failure, as he assured him that he will be able to try again with the Vanguard Action Squad at his side.

Powers and Abilities
All For One (オール・フォー・ワン Ōru Fō Wan): All For One allows him to steal people's Quirks and renders them his own. He can even combine his stolen Quirks to create destructive attacks. This Quirk also allows him to grant Quirks to others. Overall, he has stolen a variety of Quirks with his ability, including:

All For One also possess other abilities outside of his Quirk. These include: Overall, All For One is an extremely cunning, powerful villain. In his prime, he was able to reduce All Might's usage of One For All by leaving a massive, scarred wound below his chest. He is also capable of taking down other Pro Heroes with ease.
 * Search (サーチ Sāchi): All For One can observe and monitor up to 100 people at a time, including their location and weak points. This Quirk was stolen from the pro hero, Ragdoll.
 * Transmission (転送 Tensō): Similar to Kurogiri's Warp Gate, All For One is capable of producing black liquids that acts a portals. He is capable of producing multiple black liquid portals, as shown when he was transporting many Nomus into the League of Villains' hideout. This Quirk has its limits, however, as it can only warp things, depending on his location and only works if it is used on someone he shares a close relationship with.
 * Air Cannon (空気を押し出す Kūki o Oshidasu): All For One is capable of releasing an air shockwave from his arms. This Quirk's power can also be increased by combining it with other power-up Quirks, such as Musculoskeletal Coiling.
 * Forcible Quirk Activation (個性強制発動 Kosei Kyōsei Hatsudō): All For One is capable of forcefully activating someone's Quirk against their will, regardless of being conscious or not. He pulls this off by creating vein-like appendages from his fingers, which then attach to a target and activate their Quirk. This was demonstrated on Kurogiri, where All For One activated his Warp Gate and make him create a portal.
 * Impact Recoil (衝撃反転 Shōgeki Hanten): All For One is capable of reflecting the impact of an attack back at its attacker.
 * Infrared Ray (赤外線 Sekigaisen): This Quirk allows All For One sense his surroundings, as well as see through his blindness. However, he has very limited time when using this Quirk.
 * Air Walk (エアウォーク Eawōku): This Quirk allows All For One to levitate in mid air.
 * Longevity: According to All Might, All For One gained an unnamed Quirk that allows him to live for long periods of time, making him practically immortal.
 * Musculoskeletal Coiling (筋骨発条化 Kinkotsu Hatsujō-ka): This Quirk increases All For One's physical prowess, as well as increase the power of his other Quirks.
 * Proliferation (増殖 Zōshoku): All For One uses this Quirk to create multiple arms for him.
 * Hypertrophy (肥大化 Hidaika): All For One uses this Quirk to increase the size of his arm.
 * Rivet (鋲 Byō): This Quirk creates rivet-like-growths on All For One's arm.
 * Bonespear (槍骨 Sōkotsu): This Quirk creates drill-like bone structures on All For One's arm.
 * Genius Intellect: All For One has shown to possess a high degree of intelligence. Being the true mastermind behind the league, he has also been the one that's been plotting against the heroes. He also seems to have knowledge of the Quirks that he's stolen, as shown when explaining the advantages/disadvantages of his Transmission Quirk. Due to this, this allows him to use his Quirk in creative ways, as means for creating disastrous attacks.
 * Immense Strength: All For One possesses a huge degree of super strength, as he is capable of easily sending All Might flying through buildings with just his bare hands.
 * Immense Speed: All For One is extremely fast, as shown when he defeated the Pro Heroes in the League of Villains' warehouse in just a split second.
 * Immense Durability: All For One has shown to possess a extreme amount of durability. He was able to tank many hard blows from All Might, as well as his finishing move, United States of Smash.
 * Enhanced Vision: Despite losing his eyesight, All For One is able to sense his surroundings through sound, due to his hearing. He can also sense vibrations in the air.

Trivia

 * All For One's relationship with Tomura Shigaraki is identical to All Might's relationship with Izuku Midoriya. Like All Might, All For One believes that Tomura Shigaraki will not only become a great successor of the League of Villains, but a great villain in general. He also acknowledges Tomura's childish nature, leaving room for him to teach him how to become a villain. He also shows a caring side for him, as he assured that Tomura will always be able to learn from his failures.
 * Because of this, Tomura Shigaraki looks up to All For One as his ideal mentor and inspirational figure, like how Izuku Midoriya looks up to All Might.
 * Despite his childlike behaviour, it seems to be implied that All For One admires Tomura's personality in an odd way. When he defeated Best Jeanist, he refuses to take away his Quirk, as he believes that "it wouldn't fit Tomura's personality".