Warning: The following contains spoilers for My Hero Academia!!
Summary
MHA's original ending planned for Deku to transfer OFA to Bakugo, which would have been lackluster. The ending really focused on Deku, all the OFA users, and Shigaraki which made it more climactic. Deku's fight against AFO with the hero's support in the ending really cemented him as the greatest hero.
My Hero Academy's Heroes Rising is considered by many to be the best film in the series to date. Kohei Horikoshi revealed in a statement translated by Caleb Cook (MHA translator for Viz Media) that the film has an element that he wanted to use in the manga's final battle. Additionally, director Kenji Nagasaki confirmed in an interview shared by Twitter user @aitaikimochi that they used the premeditated idea of the original final battle at the end of Heroes Rising. This reveals that MHA's original ending was Deku transferring One For All to Bakugo so they can fight together.
The original ending was probably going to be a bittersweet one with Deku remaining uncharacteristic while Bakugo inherits the responsibility of continuing OFA, or it would be like the movie's ending, just a transition temporarily with Deku keeping OFA, it would have been a lackluster ending to the story.
However, chapter #423 of MHA has an ending about the battle between Deku and AFO, which proved that the true ending of My Hero Academia is a vast improvement over the original ending.
The final battle of My Hero highlights the war between OFA and AFO
Deku comprehensively defeated thanks to OFA's previous users – and Shigaraki
The original ending presented in Heroes Rising was probably a flat ending for the manga, as it followed the typical shōnen plot of the hero sharing his power with a friend or ally to fight defeat the final enemy. The true climax of the final battle in My Hero Academia remains true to the series' central conflict, which is the battle between the OFA and AFO users. The last fight stands out because Deku doesn't switch OFA to fight AFO; he did it out of a desire to save Shigaraki from himself, understand what made him a villain, and break AFO's control.
The ending proved to be better than the original because it focused not only on Deku and Bakugo but also on all OFA users and Shigaraki. Previous holders of OFA contributed to the battle in various ways: the unusual sense of danger backfired on AFO by causing him to become disoriented during the battle; The Nana Shimura relic helped maintain Shigaraki's consciousness; and a combination of attacks from both Deku in the material world and past OFA users in the relic world were what led to the AFO's defeat. Furthermore, Shigaraki, all vestiges, and Deku destroy AFO in the final attack.
Additionally, Deku's transfer of OFA gave Shigaraki a satisfying outcome because Deku didn't just defeat him with sheer power or try to redeem him. Shigaraki accepts defeat and acknowledges Deku's attempts to reach him. Shigaraki ultimately kept his faith; by not apologizing or regretting his actions, he fought to the end to follow his ideals, destroying the source of his pain—AFO and the hypocrisy in the hero world—and Finally, I die remembering my friends. Also, Shigaraki and Deku's final panel leaves the door open for Deku to keep OFA.
The true ending of My Hero Academia truly makes Deku the greatest hero
The final battle features Deku as the main character with the support of all the heroes
If the final battle used the original ending, it would strip Deku of his status as the main character of the story. Instead of just having the fight between Deku and Bakugo against the villain, it would have been a better execution to see the Class 1-A students and other heroes coming to help Deku reach the AFO. Even the AFO acknowledges the power that the heroes' unity represents.
Additionally, Deku delivers the final blow to AFO with the support of other heroes, which shows that he is a better symbol of peace than All Might because he pushes everyone forward. Overall, the actual ending of the final battle proved to be better than the original ending as it was the perfect climax to the main conflict in the story and felt great. My Hero AcademyDeku's main message is about being the greatest hero.
Source: Caleb Cook, Aitaikimochi.
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