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Boku No Hero Academia Season 1 Episode 3 detailed description :-
Izuku cries tears of joy for having his dream acknowledged by his idol. All Might tells Izuku that he is worthy to inherit his strength, and proposes to give him his quirk, confusing Izuku. All Might says that his Quirk can be passed down and has selected Izuku as his successor. All Might tells him that the name of his power is “One For All”. Izuku asks why All Might would give his Quirk to him, to which All Might replies that he doesn’t mind giving it to him and because he shined more than any of the other so-called “Heroes” during the Sludge villain’s attack on Katsuki Bakugo. After All Might’s explanation, Izuku doesn’t hesitate to accept the proposal.
All Might begins to train Izuku in order for his body to be strong enough to inherit One For All. All Might has Izuku clean the Takoba Seaside Bay of its trash as a great way to strengthen Izuku’s body for the next 10 months, as U.A.’s Entrance Exam begins by then, wanting Izuku to become a worthy vessel by that time. All Might gives Izuku an intense training schedule for the young man to follow in the coming months. During his training, Izuku overworks his body and All Might notices that he has gone beyond the schedule they had agreed on. All Might scolds him for this, fearing it will have the opposite effect they were looking for. Izuku replies that he works so hard because he wishes to excel at U.A. and become a hero just like All Might. This gives All Might a brief insight into Izuku’s passion for heroism.
After 10 months of intense training, it is now the day of U.A.’s Entrance Exam; Izuku has cleaned up Takoba Seaside Bay of its trash. As a result, Izuku’s body is now more refined and muscular, which All Might claims is now a worthy vessel for One for All. All Might gives Izuku a piece of his hair to eat, much to Izuku’s confusion. All Might says that it doesn’t matter how he takes his DNA, but due to the Entrance Exam beginning in a few hours, he needs to inherit it immediately.
Izuku arrives at U.A. High School in time for the Entrance Exam. As he is about to enter U.A., Izuku trips but is saved by a girl’s Quirk. The girl wishes him good luck, which leaves him speechless, shocked that he managed to talk to a girl.
Inside U.A., Present Mic explains how the Entrance Exam works, which begins with a practical test and then afterwards a written test saying that their goal in the practical test is to dispatch as many villains (which are actually robots) as they can to earn a high score. Izuku arrives at his designated battle centre for the practical test of U.A.’s Entrance Exam. Izuku resolves to use every ounce of power gained from All Might’s training to pass the practical test.