A hero cannot rely on his own quirk alone. Indeed, this power can inflict great physical punishment, weakening or even causing greater damage over time. For this reason, My Hero Academia has now established providers in society who offer a wide variety of solutions for every need.
The recent battles of Deku have developed it further, but also pushed it to its limits. Instead, after the interlude of Aoyama's betrayal, he went to the support area to get help, where he was greeted by an explosive Mei Hatsume. My Hero Academia 339 it gathers the legacy of the previous and takes us back to the world of hero engineering, much more now than in the past.
In Mei Hatsume's new studio, however, Deku and Iida receive poor responses to their inquiries, which are considered impossible both materially and temporally. Also, as the professor explains, Hatsume is non-stop working on the Yuei Barrier and its upgrades, explaining how busy she is. But in these few seconds, Hatsume manages to prepare useful equipment for both boys. So not a definitive costume for Deku, but a new support from Hatsume proving he's a hero just like the others fighting in the field. Back from the others, Deku and Iida get ready for the next training session.
Meanwhile, in Kansai, Tamaki and Nejire have rescued other people who will lead them to Shiketsu, the closest high school. Together with Fatgum, the two of them they speak of the war that is about to break out, this time in an open field and without cunning. Will the heroes of My Hero Academia be able to prepare with new strategies in time?