In the year 2156, amidst the era of Heroes where quirks dominate 80% of the populace and 20% remain quirkless, a transformative shift begins. A new generation of Quirkless individuals emerges, not devoid of power, but rather with mutations untethered to quirks. These mutations, distinct from quirks, offer unparalleled potency yet demand formidable control.
At the heart of this evolutionary leap lies the X Gene, awakening within select individuals across the "My Hero Academia" world. Unlike quirks, the X Gene defies detection through conventional means like the quirk detection test, presenting a challenge in identification.
Manifesting during puberty, the X Gene grants its bearers extraordinary abilities. For females, this awakening typically occurs around the ages of 8 or 9, while males experience it around 9 or 10. Once triggered, these mutations render individuals immune to quirks; any attempt to bestow a quirk results in rejection.
Among the first to showcase these mutant powers is Izuku Midoriya, bearing a mutation akin to that of Wolverine. His transformation unfolds gradually, marked by a period of debilitating illness preceding a resurgence of health by the age of 14. Enhanced senses, a robust healing factor, and eventually bone claws adorn his newfound abilities, culminating in a formidable hunter's prowess.
The pivotal moment for Izuku arrives during the training camp, where he falls into the clutches of the League of Villains, orchestrated by the nefarious All for One. Collaborating with the Hero Safety Public Commission, a procedure is devised to coat Izuku's skeletal structure with a stretchable form of adamantium. This infusion of adamantium not only fortifies his bones but also accommodates growth, ensuring Izuku's continued evolution into a force to be reckoned with.