TV-Series
Description
Speed-o'-Sound Sonic, whose Japanese name is Onsoku no Sonic, is a recurring villain and occasional anti-hero in the anime One Punch Man. He is a young man of twenty-five with a slender, somewhat androgynous appearance, medium-length black hair tied into a topknot, and two purple marks painted beneath his eyes. He typically wears a tight black ninja suit with metal plating on his chest, shoulders, forearms, and shins, along with a long scarf, and he carries a ninjato, kunai, and shuriken. He works in the underworld, taking on jobs that range from assassinations to bodyguard work, and he calls himself the strongest ninja.
In terms of background, Sonic was raised in the Ninja Village, a facility that gathered orphans and sold children and trained them from birth to become killers. He was part of its 44th Graduation Class, nicknamed The End, and trained alongside a fellow student who would later become the S-Class hero Flashy Flash. Sonic was unusual in that facility because he possessed a strong sense of self, which made him something like a dropout who received even harsher training. He and Flashy Flash once shared a dream of dismantling the village's brutal system and building a freer way of life. That dream ended when Flashy Flash, unable to endure the village's methods, carried out a massacre of its members and staff. Sonic survived as the sole survivor of the class, but he lost both his homeland and his ambitions, and he turned to the only skill he had left, the art of killing. This history explains his contempt for heroes, whom he views as people who claim grand ideals while possessing power that does not match their words.
Personality-wise, Sonic appears calm and composed on the surface, but he is cold-blooded, ruthless, and extremely proud. He has an absolute confidence in his speed and techniques, and he reacts violently to anyone who sees through his moves or acts arrogantly toward him. He is also a genuine battle maniac who feels excitement when testing his skills against strong opponents, sometimes breaking into a childish or distorted smile in the middle of combat, a habit he himself acknowledges as a bad one. He can kill without hesitation, as shown when he cut down members of the Paradise Group without a moment's pause, and he is willing to drag civilians into his fights. At the same time, he shows a stubborn, almost earnest side in his dedication to training and self-improvement, and he holds to a personal rule of never letting an opponent he has fought live.
His central motivation is his rivalry with Saitama. Sonic first appears as a bodyguard hired by the wealthy Zeniru, assigned to deal with the Paradise Group. While pursuing one of its members, he encounters Saitama and attacks him without explanation, only to have all of his techniques easily read and countered. The encounter ends with Saitama accidentally striking him in the groin, a humiliating defeat that Sonic cannot accept. From that point on, he declares Saitama his eternal rival and dedicates himself to finding a way to defeat him. He frequently reappears to challenge Saitama, each time having developed a new technique, and each time being defeated again, sometimes in ways that Saitama does not even fully register as a fight. Saitama, for his part, does not take the rivalry seriously and even misremembers Sonic's name, but Sonic's obsession remains the consistent engine of his actions.
In the story, Sonic functions as a dangerous independent force outside both the Hero Association and the monster side. He serves as a recurring threat whose speed and skill make him a serious opponent for most characters, while his repeated failures against Saitama highlight the absurd gap between Saitama and everyone else. He has also clashed with or encountered other major figures. He fights the Deep Sea King and manages to avoid its attacks but lacks the power to finish it. He battles Genos, Saitama's disciple, in a fight that reaches a stalemate because Sonic's attacks cannot damage Genos's armor while Genos cannot land a hit on Sonic. He later reunites with Flashy Flash and, despite their unresolved grudge, fights alongside him against the Ninja Party, an organization of surviving ninja from the village, and the pair display a flawless coordination that surprises even themselves. Sonic also shows reluctance to become a monster even when tempted, most notably when he obtains a monster cell intended to grant him greater power but cooks and eats it instead, which neutralizes its effect and only gives him a stomach ache.
Over the course of the series, Sonic develops from a cold professional killer into an obsessive but increasingly capable rival. Every defeat pushes him to train harder and invent new techniques, and his stubborn persistence is shown to be genuine strength. Later in the story, he obtains scrolls and weapons left by the founder of the Ninja Village, which allow him to grow even stronger. With these, he overwhelms a group of Neo Heroes led by a hitman known as Ea, defeats twenty-nine enemies in an instant using an electrified strike, and even takes down a dragon-level threat in the form of the machine god Shunpo, a feat that places his power on par with multiple S-Class heroes. His development is characterized by the contrast between his deadly serious pursuit of strength and the absurd ways in which that pursuit keeps failing against Saitama.
In terms of notable abilities, Sonic possesses superhuman speed and agility that allow him to move faster than most characters can even track, with full-speed running generating shockwaves. He can create multiple afterimages of himself using special footwork, producing techniques such as the Four Shadows Burial, an upgraded Ten Shadows Burial, and a later Thirteen Shadows Burial, in which he splits into multiple afterimages to deliver simultaneous attacks. He has a wide arsenal of ninja skills, including substitution techniques, smoke screens, and a variety of explosive shuriken techniques, such as wide-area bombardment, homing projectiles, and smoke-releasing shuriken. He also uses powerful kicks and, after acquiring the founder's hidden techniques, a lightning-imbued punch capable of dispatching large groups of enemies at once. His main limitations are his relatively light attack power against heavily armored or extremely durable foes and his dependence on his weapons, as he can be forced into a retreat when deprived of them. Overall, Sonic is a skilled and dangerous fighter whose defining trait is his unwavering, and often comically one-sided, obsession with surpassing Saitama.
In terms of background, Sonic was raised in the Ninja Village, a facility that gathered orphans and sold children and trained them from birth to become killers. He was part of its 44th Graduation Class, nicknamed The End, and trained alongside a fellow student who would later become the S-Class hero Flashy Flash. Sonic was unusual in that facility because he possessed a strong sense of self, which made him something like a dropout who received even harsher training. He and Flashy Flash once shared a dream of dismantling the village's brutal system and building a freer way of life. That dream ended when Flashy Flash, unable to endure the village's methods, carried out a massacre of its members and staff. Sonic survived as the sole survivor of the class, but he lost both his homeland and his ambitions, and he turned to the only skill he had left, the art of killing. This history explains his contempt for heroes, whom he views as people who claim grand ideals while possessing power that does not match their words.
Personality-wise, Sonic appears calm and composed on the surface, but he is cold-blooded, ruthless, and extremely proud. He has an absolute confidence in his speed and techniques, and he reacts violently to anyone who sees through his moves or acts arrogantly toward him. He is also a genuine battle maniac who feels excitement when testing his skills against strong opponents, sometimes breaking into a childish or distorted smile in the middle of combat, a habit he himself acknowledges as a bad one. He can kill without hesitation, as shown when he cut down members of the Paradise Group without a moment's pause, and he is willing to drag civilians into his fights. At the same time, he shows a stubborn, almost earnest side in his dedication to training and self-improvement, and he holds to a personal rule of never letting an opponent he has fought live.
His central motivation is his rivalry with Saitama. Sonic first appears as a bodyguard hired by the wealthy Zeniru, assigned to deal with the Paradise Group. While pursuing one of its members, he encounters Saitama and attacks him without explanation, only to have all of his techniques easily read and countered. The encounter ends with Saitama accidentally striking him in the groin, a humiliating defeat that Sonic cannot accept. From that point on, he declares Saitama his eternal rival and dedicates himself to finding a way to defeat him. He frequently reappears to challenge Saitama, each time having developed a new technique, and each time being defeated again, sometimes in ways that Saitama does not even fully register as a fight. Saitama, for his part, does not take the rivalry seriously and even misremembers Sonic's name, but Sonic's obsession remains the consistent engine of his actions.
In the story, Sonic functions as a dangerous independent force outside both the Hero Association and the monster side. He serves as a recurring threat whose speed and skill make him a serious opponent for most characters, while his repeated failures against Saitama highlight the absurd gap between Saitama and everyone else. He has also clashed with or encountered other major figures. He fights the Deep Sea King and manages to avoid its attacks but lacks the power to finish it. He battles Genos, Saitama's disciple, in a fight that reaches a stalemate because Sonic's attacks cannot damage Genos's armor while Genos cannot land a hit on Sonic. He later reunites with Flashy Flash and, despite their unresolved grudge, fights alongside him against the Ninja Party, an organization of surviving ninja from the village, and the pair display a flawless coordination that surprises even themselves. Sonic also shows reluctance to become a monster even when tempted, most notably when he obtains a monster cell intended to grant him greater power but cooks and eats it instead, which neutralizes its effect and only gives him a stomach ache.
Over the course of the series, Sonic develops from a cold professional killer into an obsessive but increasingly capable rival. Every defeat pushes him to train harder and invent new techniques, and his stubborn persistence is shown to be genuine strength. Later in the story, he obtains scrolls and weapons left by the founder of the Ninja Village, which allow him to grow even stronger. With these, he overwhelms a group of Neo Heroes led by a hitman known as Ea, defeats twenty-nine enemies in an instant using an electrified strike, and even takes down a dragon-level threat in the form of the machine god Shunpo, a feat that places his power on par with multiple S-Class heroes. His development is characterized by the contrast between his deadly serious pursuit of strength and the absurd ways in which that pursuit keeps failing against Saitama.
In terms of notable abilities, Sonic possesses superhuman speed and agility that allow him to move faster than most characters can even track, with full-speed running generating shockwaves. He can create multiple afterimages of himself using special footwork, producing techniques such as the Four Shadows Burial, an upgraded Ten Shadows Burial, and a later Thirteen Shadows Burial, in which he splits into multiple afterimages to deliver simultaneous attacks. He has a wide arsenal of ninja skills, including substitution techniques, smoke screens, and a variety of explosive shuriken techniques, such as wide-area bombardment, homing projectiles, and smoke-releasing shuriken. He also uses powerful kicks and, after acquiring the founder's hidden techniques, a lightning-imbued punch capable of dispatching large groups of enemies at once. His main limitations are his relatively light attack power against heavily armored or extremely durable foes and his dependence on his weapons, as he can be forced into a retreat when deprived of them. Overall, Sonic is a skilled and dangerous fighter whose defining trait is his unwavering, and often comically one-sided, obsession with surpassing Saitama.