Episode 23

"Shoto Todoroki: Origin" is the twenty-third episode of the My Hero Academia anime and the tenth episode of the second season.

Summary
The fated duel between Izuku and Shoto has finally arrived. As soon as it begins, Shoto leads with an ice attack, but Izuku counters with a Delaware Smash. Shoto creates a pillar of ice behind him to keep him from being blown out of bounds, as he expected Izuku to break his finger in order to negate the ice attack.

All Might comments that this was likely the only way Izuku could have retaliated. Izuku is forced to damage a second finger to stop Shoto's next attack and mulls over that he only has six more chances, and must find Shoto's weakness before he breaks all his fingers. Shoto doesn't let up and continues his onslaught of ice attacks.

In Class 1-A's section of the stands, Eijiro returns from defeating Tetsutetsu. He sarcastically compliments Katsuki and Shoto for having techniques that blast the whole stadium. Katsuki responds by explaining that Quirk's are physical abilities and can get worn out just like anything else. He takes a moment to ponder that this is the very reason he designed his costume in such a way so that he could go beyond his own limits.

Shoto's assault continues, forcing Izuku to break the last finger on his right hand. However, Shoto withstands the smash and creates a tower of ice to run up and close the distance between them. Izuku uses another smash to break the ice steps a part, but Shoto avoids it and nearly freezes Izuku at close range.

In order to break the ice that's slowly freezing him, Izuku sacrifices his entire left arm and lets off a full powered smash. Shoto withstands the aftershock of the smash using an ice blockade. While recovering, Shoto notes that this attack from Izuku was significantly more powerful the previous ones and that he realizes his opponent is trying to keep him at a distance. Izuku is startled by Shoto's combat awareness, and some viewing fans even comment that Shoto is already stronger than the average pro hero.

Questioning Izuku's durability, Shoto asks if he's already too worn out from defending against the ice. Izuku doesn't respond, and instead he notices that Shoto is shaking because of the frost that building up on the right side of his body. Shoto apologizes for the intensity of the battle and thanks Izuku for helping him irritate Endeavor by only using ice rather then fire. Understanding that Izuku has no healthy fingers left, Shoto sends an ice attack at him that he expects to finish the match. However, Izuku declares that he isn't finished yet and uses his already broken finger to blow Shoto's ice away.

Shoto asks why Izuku is going so far. Izuku replies that Shoto is trembling and points out that Shoto's body can only take so much cold because Quirk's are physical abilities. He also surmises that Shoto could offset his temperature by using his fire, but knows Shoto refuses to do so. He challenges Shoto to put more effort into the battle, stating that everyone else is giving it their all while Shoto is only using half his power. Izuku provokes Shoto by claiming that he has yet to injure him in this battle, demanding that Shoto use his full strength.

Agitated, Shoto rushes Izuku, albeit much slower than before. Katsuki notices Shoto's drop in mobility and assumes that it's because Shoto's stamina is running low after wasting so much of it fighting Hanta. Shoto closes in on Izuku, but as soon as he lifts his right foot to attack, Izuku controls All For One and strikes Shoto in the torso, sending him flying away. Shoto recovers and tries to use another ice attack, but it's much slower than the previous ones and Izuku is able to avoid it. They both move into closer quarters and fight in spite of their afflictions. Cementass urges Midnight to stop the match because Izuku is fighting too recklessly by continuing to injure his already broken fingers with more smashes. Aizawa retorts that Izuku isn't fighting recklessly, he's simply doing everything he can to win the match within his current skill level. He also commends Izuku for his resolve and on ponders his student's intent.

As Izuku dashes at Shoto, the latter attempts to freeze him. Without any fingers left to use, Izuku pulls back his thumb using his cheek in order to release another smash to blast Shoto away. Shoto asks again why Izuku is putting himself through so much pain, to which his opponent replies is because he's prepared to do whatever it takes to become a hero. After headbutting Shoto, Izuku again challenges him to use his full strength, telling him to stop screwing around because even if he wants to reject his father, Shoto doesn't have the right to be the best if he's not prepared to do his best.

Izuku's words make Shoto recall the terrible memories of his past. As more frost covers his body, Shoto remembers he and his mother being abused by Endeavor. As well as a time where he pleaded to his mother about not wanting to become like his father, to which she replies by asking if Shoto still wants to become a hero. Izuku capitalizes and strikes Shoto with another controlled One For All punch, and declares that he will surpass him.

While reeling from the attack, Shoto is reminded of his childhood. He remembers that as a child he was constantly separated from his siblings, and when his mother finally went mad from all the domestic abuse and burned his face. Endeavor had her put into a psychiatric ward, but Shoto blames him for his mother's breakdown. Still haunted, Shoto states once again that he will reject his father, but this time Izuku adds that Shoto's Quirk is his own, and not his fathers. This invokes one last memory, one that Shoto had long forgotten. He and his mother were sitting down watching a special on TV about All Might. All Might encourages all children to use their Quirk's in their own way in spite of inheriting them from their parents. Shoto's mother adds that Shoto must remember to stay true to himself, that he is not a prisoner of his lineage, and that it's okay to use his power to become who he wants to be.

Impassioned, Shoto decides to trigger his fire power and astounds the entire arena with his display of blazing power. All Might recognizes that Izuku had been trying to provoke Shoto to this point in order to save him from rejecting not only half his power but half of himself. As the flames die down and the ice melts from Shoto's body, he says that now Izuku is the one screwing around for helping his opponent. Shoto adds that just like Izuku, he desires to become a hero one day too. Having freed Shoto from his self-repression, Izuku smiles and comments that Shoto's power is amazing to which he responds with an affecting smile of his own.

Ecstatic, Endeavor shouts proudly about Shoto finally using his fire power. He walks down closer to the match and claims that Shoto will surpass him and live up to the reason for his birth. With the battle reaching its climax, Shoto asks why Izuku is grinning in such a hopeless situation with his injuries and pleads for Izuku not to blame him for what happens next.

They both power up in preparation for one final clash. Cementoss and Midnight decide to step in, fearing one of them might die. Shoto sends a large wave of ice at Izuku, but the latter jumps above it by using One For All in his leg. As he flies towards Shoto, he prepares a full power smash in his healthy arm, and Shoto counterattacks with a powerful fire blast, thanking his opponent as he does so. Even though Cementass builds a wall between them, Izuku's wind pressure and Shoto's fire create an explosion that destroys the entire fighting ring.

Everyone watches in pure disbelief, and after he recovers, Cementoss commends both of them for their talent. Present Mic asks what caused the explosion, to which Aizawa replies that it was caused by the rapidly changed temperature in the arena. The smoke clears, and Izuku is revealed to be unconscious outside the ring. Everyone is taken back by the battle's outcome, and Midnight announces that Shoto Todoroki is the victor.