Midoriya inherits the superpower of the world's greatest hero, but greatness won't come easy. 
What would the world be like if 80 percent of the population manifested superpowers called "Quirks"? Heroes and villains would be battling it out everywhere! Being a hero would mean learning to use your power, but where would you go to study? The Hero Academy of course! But what would you do if you were one of the 20 percent who were born Quirkless? 
In the desperate battle with All For One and his minions, the U.A. students are pushing themselves to their absolute limits. Everywhere, the villains have the upper hand. As the floating U.A. island falls out of the sky, Ochaco and Asui fight Himiko Toga, and Midoriya squares off with Tomura. All For One's new form appears all but unstoppable, and if he reaches Tomura, all is lost. But one hero stands in his way...