There's no way to know for sure without reading the fanfiction. However, it could potentially be a side character that the author has decided to make the focus. For example, a character who has always been in the background but suddenly their disappearing act becomes the central mystery. It could also be a hero who has been mentioned briefly in the original series but is now given a whole new story arc in this fanfiction where their disappearance is the key plot point.
It could be about a hero in the My Hero Academia universe who is disappearing for various reasons, like perhaps a quirk malfunction, a secret mission that requires them to go incognito, or they might be under some sort of threat that is causing them to vanish from the public eye.
Bakugo could also make an interesting main character. His explosive personality combined with a gamer ability would be really cool. He could be super competitive in the 'gamer' aspects of the story, like ranking up in a hero - ranking system that works like a game. And he would be all about proving he's the best, not just in real - life heroics but also in the game - like challenges.
It could be a new student at U.A. High School. A cyborg with a unique quirk related to their mechanical parts, like the ability to fly using jet - propelled limbs. This character could be the main focus as they learn to control their powers and make friends among their classmates.
It could be a new student at U.A. High School. This student, with the 'Heroic Timing' quirk, is trying to fit in among the more well - known and powerful quirks. They might face some initial ridicule or underestimation from their classmates, but as they start to show the true value of their quirk during training exercises and real - life hero situations, they gain respect.
It could be Deku. Since he is the main protagonist in the original My Hero Academia series, it would make sense for him to be the main character in this fanfiction as well. He could be the one who discovers the 'Flames of Hope' power and has to learn how to control it while still using his One For All ability.
All Might could also be an interesting choice. If someone was reincarnated as a younger All Might, they could change some of the events that led to his decline in health. They could also learn from his mistakes and become an even more powerful and long - lasting symbol of peace.
Izuku Midoriya could be a great main character in a magic - infused fanfiction. Imagine if he discovers he has an innate magical ability on top of his One For All quirk. He could use magic to further enhance his physical abilities or develop new techniques. His determination and growth throughout the story would be even more exciting with the addition of magic.
It could be Deku. Since he is the main character in the original series, it would be interesting to see how he adapts to the new management system. Maybe he could be at the forefront of advocating for changes that benefit all students.
It's hard to determine a single strongest character as it depends on various factors. Deku has great potential with One For All and Shigaraki has become a major threat with his evolving powers.
I think Icarus is the central figure in this fanfiction. But characters like Midoriya Izuku would also be important. Izuku's journey as a hero - in - training could be intertwined with Icarus'. Maybe they become friends or rivals. And villains from My Hero Academia, such as Tomura Shigaraki, could also be main characters. His evil plans might be affected by or target Icarus, adding more drama to the story.