Chapter 123

Invincible (無敵) is the one hundredth and twenty third chapter of Kohei Horikoshi's Boku no Hero Academia Manga.

Summary
U.A's Big Three have arrived to teach Class 1-A about Hero Internships. Izuku Midoriya remembers the male with the weird face from last year's Sports Festival and notes that he did not display any notable results. Izuku also remembers that the other two did not finish in the top of the Sports Festival and wonders what Heroes the Big Three are.

Shouta Aizawa asks Tamaki Amajiki, the male U.A student with the messy black hair and pointy ears, to introduce himself. Tamaki glares at Class 1-A which sends a shiver down some of their spines. Tamaki appears to be unimpressed with Class 1-A, seeing everything but their heads (which are potatoes from his perspective) as human. Due to being unable to see them as anything but human, Tamaki places his head against the blackboard and desires to go home. Class 1-A are perplexed at Tamaki's strange behavior. The female introduces herself as Nejire Hadou and wants to talk about Hero Internships with Class 1-A. However, Nejire instead asks questions pertaining to some of Class 1-A's unique features due to her curiosity; Nejire asks about Mezou's mask, Shouto's burn, Mina's horns, Minoru's hair, Tsuyu's frog species, and Mashirao's tail. Shouta sees that U.A's Big Three lacks rationality. Mirio Toogata, the last of U.A's Big Three, tells Shouta not to worry as he is the star performer today.

Mirio yells out, "The journey ahead," which confuses Class 1-A. Mirio tells Class 1-A that they were supposed to respond with "will be full of difficulties." Some of Class 1-A find U.A's Big Three to be weird. Mirio sees that Class 1-A do not understand what is going on and tells them that he understands that feeling. Mirio comments that Class 1-A is energetic due to them receiving their Provisional Hero Licenses as first years. Seeing that his introduction has fell flat, Mirio offers Class 1-A the chance to team up together and fight him, much to Class 1-A's surprise. Mirio decided to challenge Class 1-A because having them witness their experiences personally would be better than a simple explanation. Shouta tells Mirio to do as he pleases.

At Gym Gamma, Hanta Sero asks Mirio if he really wants to fight all of Class 1-A at the same time, to which Mirio replies that he is serious. Tamaki, who is placing his head against a wall, informs Mirio not to discourage Class 1-A with his skills. While playing with Mina's horns, Nejire notes that Mirio had a rough time as a child and warns Class 1-A to think things through before attacking Mirio. Fumikage Tokoyami and Eijirou Kirishima note that they have the advantage and Eijirou asks Mirio if he sees them as nothing but small fry, to which Mirio replies he does. Mirio tells Class 1-A to attack him whenever, wherever they want and asks who wants to go first. Izuku and Eijirou decide to go first. Surprised at Izuku's determination, Eijirou lets Izuku go first.

Izuku activates One For All Full Cowl and charges at Mirio while the rest of Class 1-A prepare their Quirks. Suddenly, Mirio's clothes fall off, which surprises some of Class 1-A. Mirio apologizes as it is difficult for him to adjust his clothing correctly. Izuku sees that Mirio is full of openings and kicks Mirio in the face with a One For All enhanced kick. However, Izuku's enhanced kick phases through Mirio. Izuku is surprised that Mirio has an intangibility Quirk. Mirio is attacked by Hanta's Tape, Mina's Acid, and Yuuga's Navel Laser, but all their attacks phase through Mirio, leaving him completely unharmed. After the attacks dissipate, Mirio has disappeared. Out of nowhere, Mirio appears behind Kyouka Jirou and prepares to attack her. Eijirou is surprised that Mirio's Quirk allows him to teleport as well. Tamaki notes that Class 1-A should not be jealous of Mirio's Quirk but rather his incredible technique; after being scouted, Mirio completely devoted himself to his internship under a certain Hero and was carefully cultivated.

Using a combination of his Quirk and technique, Mirio has defeated half of Class 1-A within a few minutes; Mezou, Denki, Kyouka, Mina, Fumikage, Momo, Tsuyu, Yuuga, Minoru, and Hanta. Shouta tells Class 1-A to take this great opportunity and learn from it because as he knows it, Mirio Togata is the closest man to becoming the Number One Hero which includes the Pro Heroes as well, which shocks the rest of Class 1-A.