Toshinori Yagi, revered as All Might, rises from a Quirkless childhood to become the towering Symbol of Peace. Nana Shimura, the seventh wielder of One For All, selects him as her successor following her tragic demise at All For One’s hands—a defining loss that ignites his unyielding crusade against injustice. Under Gran Torino’s tutelage, Toshinori hones One For All’s power, crafting the All Might persona to galvanize hope and slash Japan’s crime rates to unprecedented lows. At his zenith, All Might’s might peaks at Mach 10, though he tempers his strength to safeguard bystanders. His heroic guise—a brawny, comic book-hero silhouette—clashes starkly with his true form: a frail, skeletal figure carved by a devastating injury from All For One. This wound ravages his respiratory system and stomach, confining his heroics to three daily hours as he hides his frailty to preserve public hope. Forced into retirement after expending One For All’s remnants in a climactic clash with All For One, he channels his wisdom into teaching Foundational Hero Studies at U.A. High. Here, he mentors Izuku Midoriya, a selfless Quirkless student he deems worthy of inheriting One For All. Guiding Izuku, he stresses strategic control over brute force, reshaping his successor’s path from his own early missteps. All Might’s costumes mirror his evolving legacy—from caped classicism to sleek modernity. His final battle during the Final War sees him piloting Hercules, a high-tech armor forged from his car. Though the suit buckles under All For One’s assault, costing him his legs and briefly confining him to a wheelchair, rehabilitation later restores his mobility. Eight years on, his iconic grin and white sclerae endure, etched with age yet undimmed. Publicly, All Might radiates exuberance, rallying crowds with booming mantras like “PLUS ULTRA!” and “I am here!” Privately, his emaciated form harbors quiet doubt and chronic pain, a testament to sacrifices made for societal stability—a creed imparted by Nana Shimura. This duality of indomitable icon and vulnerable man underscores heroism’s hidden costs. Spin-offs like *My Hero Academia: Vigilantes* glimpse his early career, revealing how his pre-series influence anchored a turbulent society. Post-retirement, his legacy thrives through Izuku and peers, who blend his ideals with fresh innovation. The Hercules battle—a Quirkless triumph of grit over power—seals his arc, proving heroism’s core lies not in abilities but unyielding resolve. His journey, from solitary guardian to mentor, champions collective resilience as the true cornerstone of peace.