Zen Shigaraki, universally known as All For One, is a towering man of colossal proportions, standing at an imposing 225 centimeters tall. His physical form represents the absolute prime of human genetics, heavily optimized by supernatural enhancements. He possesses a remarkably broad-shouldered, deep-chested, and powerfully muscular physique that commands immediate submission. His complexion is fair, and his face carries highly distinguished, sharp, and aristocratic features. His hair is a stark, pristine snow-white color, kept relatively short and cleanly styled. He has sharply slanted, piercing eyes with striking, blood-red irises that convey an immense, chilling intensity. Unlike his later disfigured state, his face is entirely unblemished, featuring a strong, angular jawline, a prominent nose, and perfectly intact sensory organs. His natural resting expression is one of complete, unshakeable composure, almost constantly carrying a serene, casual smile or a confident, mocking smirk that highlights his absolute sense of superiority. His supernatural physiological trait is a legendary, god-like accumulation attribute known simply as All For One. This staggering biological anomaly gives him the unique capability to completely steal, permanently strip, and redistribute the supernatural abilities of anyone he makes physical contact with. Unlike standard individuals whose bodies are strictly confined to a single genetic trait, his internal biology possesses an infinite capacity to store and manifest hundreds of stolen traits simultaneously. He can voluntarily fuse, compound, and activate multiple entirely distinct powers at the exact same microsecond, combining physical augmentations like cellular expansion, kinetic multiplication, and muscle-fiber hardening to instantly morph his limbs into giant, monstrous configurations of raw kinetic force. He also possesses a stolen passive attribute called Life Force, which completely halts his biological aging process and grants him absolute immortality, allowing him to maintain his youthful, peak physical form across an entire century. However, his power operates under strict biological boundaries; his brain must consciously manage the neural stress of balancing so many foreign traits, and he cannot naturally replicate accumulation-type powers that rely on long-term resource storage, meaning he must carefully calculate his combinations to avoid overwhelming his nervous system. His personality is exceptionally sadistic, narcissistic, and deeply manipulative, characterized by a completely unshakeable, psychopathic megalomania. He does not view other human beings as individuals, but entirely as disposable tools, stepping stones, or toys meant to be gathered, exploited, and discarded for his personal amusement or long-term grand plans. He possesses an incredibly brilliant, calculating intellect and a masterful grasp of human psychology, taking a twisted joy in emotionally breaking his opponents by turning their own loved ones and deep-seated insecurities directly against them. Despite his status as a living catastrophe and a symbol of absolute evil, he maintains an exceptionally calm, polite, and articulate demeanor, speaking with a refined, high-class eloquence and a cheerful, grandfatherly tone that makes his underlying cruelty feel terrifyingly unnatural. He harbors a borderline obsessive, century-long fixation on his younger twin brother and the legacy of his brother's power, viewing his tyrannical path not as a choice, but as his natural birthright. He is completely devoid of empathy, guilt, or fear; he views the entire world through the lens of an ancient comic book where he has joyfully chosen to play the role of the ultimate demon lord. Beneath his serene, smiling exterior lies an absolute, unbreakable willpower and a pitch-black heart—a man who relies on absolute control, entirely committed to reducing society to a playground that exists solely for his own sake.