Episode 28

Midoriya and Shigaraki (緑谷と死柄木)is the twenty-eighth episode of the My Hero Academia anime and the fifteenth episode of the second season.

Summary
Gran Torino tells Izuku that if he can move while having One For All coursing through his body, then he will be at a completely different level then he was during the Sports Festival. Then he gives him three minutes to try and land a smash in his new state.

As soon as their mock battle begins Gran Torino stops the flow of One For All's power by striking Izuku from several angles. Unable to counter due to Gran Torino's speed, Izuku hides underneath a table to buy enough time to activate One For All Full Cowl. Gran Torino moves to attack the couch, but Izuku sends it flying at him, giving him enough time to re-activate his new power.

Izuku leaps into the air and nearly hits the old man, but Gran Torino is able to counter and get behind Izuku. Thanks to his newfound menueverability, Izuku evades by jumping above Gran Torino and tries to use a smash on him. Once again Gran Torino proves to be too fast and just narrowly dodges the smash before headbutting Izuku into a wall.

The old man informs Izuku that his three minutes are up and Izuku laments over his inability to maintain One For All Full Cowl. Gran Torino replies that Izuku has already improved since their bout the previous day. He thinks to himself about how Izuku may turn out be amazing after actually managing to graze his cheek and force him to dodge seriously. They plan on continuing training after breakfast, but all of the food was spilled onto the ground, forcing Izuku to run out to get more.

Meanwhile, Izuku's classmates continue interning at their respective agencies. Ochaco trains her body with Gunhead while Fourth Kind scolds Eijiro and Tetsutetsu for making lukewarm coffee. Katsuki regrets his decision as Best Jeanist styles his hair and lectures him about having the appearance of an elegant hero. Momo and Itsuka continue to shadow Uwabami, still trying to understand the bigger lesson in accompanying her to all of her side jobs.

At U.A. High, Detective Tsukauchi meets with All Might to discuss what he's learned about Nomu. The Police Force has deduced that Nomu was formally a low level thug who's been bioengineered to hold multiple Quirks at once. His brains processing power has been reduced because of this, making Nomu unable to think for himself. Naomasa explains that despite having multiple peoples DNA, Nomu still shouldn't have various Quirks. He theorizes that someone else has the ability to grant other people Quirks. Astonished, All Might transforms into his hero form and states his concern that perhaps he is back again.

Elsewhere, Stain has overpowered Tomura and Kurogiri at their hideout. He states that the League of Villains will always be aimless weaklings without convictions. Tomura tries to order Kurogiri to send Stain away, but he is unable to move due to Stain's Quirks. As Stain's knife draws closer to the palm on his face, Tomura gets angry and grabs the knife, disintegrating it. He states that if the world wants to worship All Might, then he'll crush the symbol of peace and then the entire world. Stain leaps back and agrees that they both desire to destroy the present and he will allow Tomura's warped convictions to grow. Tomura doesn't want Stain to join the league, but Kurogiri pleads for him to reconsider. Stain asks to be returned to Hosu City so that he can purge the remaining fake heroes there.

In Hosu City, Tenya surmises that Stain will follow the pattern of attacking four heroes in every city he shows up in. He's only attacked Tensei in Hosu, so Tenya figures that he will appear again, and when he does Tenya plans on disposing of the Hero Killer himself. Back at Gran Torino's apartment, the retired hero decides to take Izuku out to fight real villains to avoid developing weird habits from training together. He plans on getting Izuku experience by fighting different types of villains and leads him to the train station to travel to Tokyo. Izuku notes that their train will pass Hosu City and plans to try and contact Tenya.

Tenya continues to patrol the streets with Manual, and the Pro Hero asks him if he's actually pursuing the Hero Killer. He's surprised that Manual was able to figure it out. Then Manual lectures him that Pro Heroes must never use their Quirks for their own selfish desires. Tenya replies that he understands, but he mulls about his burning hatred. Tomura and Kurogiri follow Stain to the city. After they further discuss Stain's goal to destroy false heroes, Stain moves to attack more Pros. Kurogiri tries to explain that Stain's work has been effective, but Tomura refuses to join up with him and orders three new Nomu's to attack the city in order to destroy the Hero Killer.

While passing through House City, Gran Torino tells Izuku that it will be more fun arriving later in the night because their will be more fights breaking out. Izuku takes a moment to text Tenya, but doesn't receive a reply. Then suddenly one of the trains passengers comments that a building as exploded and one of the Nomu's breaks into the train, having overpowered a Pro-Hero. Gran Torino leaps into action and tackles the Nomu out of the train and into the city. Izuku cries out his mentors name just as he notices several areas of the city going up in flames. Manual and Tenya rush to try suppress the conflict, but Tenya notices the Hero Killer in an alleyway.

Stain prepares to finish off the Pro-Hero Native and Tenya saves him by drawing the villain's attention. Tenya tries to kick Stain, but he uses his katana to counter and knock Tenya's helmet off. He warns Tenya to leave because even children may becoming his targets. Tenya furiously replies that Stain is the criminal that attacked his older brother, and that he will defeat him in Ingenium's place as the successor to his siblings moniker. Stain notices Tenya's vengeful intent, and tells the young man to prepare to death.