Saitama
17Saitama is the main protagonist in One Punch Man, as well as the most powerful hero alive. As the title suggest, he is able to defeat any monster he comes up against in one punch. Due to this he faces a self-imposed existential crisis, as he is too overwhelmingly powerful to gain any thrills from his battles. He registers in the Hero Association along with his sidekick Genos.Demon Cyborg
11Genos is a 19-year old cyborg and one of the main protagonists of One-Punch Man. He is the self-proclaimed disciple of Saitama, as well as a hero under the hero association. He is currently serving as S-Class rank 14 and goes by the alias "Demon Cyborg"Sneck
6Sneck is an A-Class Superhero, rank 37.Tanktop Master
6Tanktop Master is the S-Class, Rank 15, superhero for the Hero Association.Metal Knight
6Bofoi is an S-Class, rank 6, superhero for the Hero Association.Metal Bat
6Metal Bat is a S-Class, rank 16, superhero for the Hero Association.Bang
5Garou
5Garou is a former student of Bang, a famous martial arts master. After rampaging and getting kicked out of the dojo, he embarks on a journey to become the most powerful and the most evil monster ever. He is a self-declared God level threat, and amongst the most power characters in the series. He is also the main antagonist of the Hero Hunt arc on and one of several antagonists in the Monster Association arcTatsumaki
5Tatsumaki is the S-Class rank 2 hero of the Hero Association, as well as the older sister of Fubuki. She is a loli and an esper, and among one of the most powerful characters in the seriesMumen Rider
5Mumen Rider is a C-Class Rank 1 superhero from Z-City.Lightning Max
5Lightning Max is an A-Class, rank 19, superhero for the Hero Association.Child Emperor
5Child Emperor is a S-Class, rank 5, superhero for the Hero Association.Watchdog Man
5Watchdog Man is an S-Class Rank 12 hero.Sonic
4Puri-Puri Prisoner
4Hellish Blizzard
4Fubuki (aka Blizzard of Hell) is a proffesional B-rank hero of the hero association. She is younger sister of the S-Class hero Tatsumaki and is the leader of the B-rank faction known as The Blizzard GroupIaian
4Iaian is the A-Class Rank 2 superhero and a disciple of Atomic Samurai.Atomic Samurai
4Atomic Samurai is a S-Class, rank 4, superhero for the Hero Association.Suiryu
4Suiryu is a martial artist and user of the Void Fist.King
3Stinger
3A-class hero.Lightning Genji
3A-class hero.Sweet Mask
3Sweet Mask is a famous model, actor, singer and both, the highest ranked A-Class hero of the Hero Association, as well as the most popular one in the world.Zombieman
3Zombieman is a S-Class Rank 8 superhero for the Hero Association.Drive Knight
3Drive Knight is an S-Class Rank 9 superhero the Hero Association.Flashy Flash
3Flashy Flash is a S-Class, Rank 13, Superhero for the Hero Association.Lord Boros
2Leader of the space pirate gang 'Dark Matter', Lord Boros is a superpowered alien being who scours the universe looking for a worthy foe to do battle with.Deep Sea King
2The Deep Sea King, also known as "Sea King" was the sovereign ruler of the Seafolk and was the most powerful of them all. He was also the main antagonist of the Sea Monster Arc and defeated several heroes before meeting his end at the hands of Saitama.Lily
2Lily is a B-Class Superhero and member of the Blizzard Group.Okamaitachi
2Okamaitachi is the A-Class rank 3 superhero for the Hero Association and a disciple of Atomic Samurai.
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