One-Punch Man Wiki

Angry Grandpa (マジギレ, Majigare) was a Mysterious Being that appeared in the audiobook, Sonic, Becoming Saitama. He was killed by Speed-o'-Sound Sonic.[1]


Angry Grandpa used to look like a regular human before transforming into a monster.


Angry Grandpa hated rowdy children. He would attack children for being rude. An example of this hatred is that he said: "I’m gonna teach all the kids around here a lesson in manners! And make sure none of them ever try to do whatever they want again like it’s a game!"


Pushed over the edge by screaming kids and loud music in public, Angry Grandpa became a monster.



Sonic, Becoming Saitama[]

Angry Grandpa fights Mumen Rider, but is eventually taken out by Speed-o'-Sound Sonic, who is disguised as Saitama.

Abilities and Powers[]

Angry Grandpa was able to put up a fight against Mumen Rider but was easily taken out by Speed-o'-Sound Sonic.

Physical Abilities[]

Enhanced Strength: Angry Grandpa was strong enough to punch holes in the ground.[1]

Enhanced Durability: Angry Grandpa could withstand bullets from police-grade firearms to no apparent damage.[1]

Frustration Accumulation: As Angry Grandpa accumulated frustration, he could unleash bursts of immense power.[1]

Fighting Style[]

Hand-to-Hand Combatant: Angry Grandpa fought Mumen Rider in close quarters.

  • Furious Outburst Punch: The punch was strong enough to destroy concrete.[1]




Mysterious Beings
Dragon (or higher) Boros Orochi *
Demon 170,000-Year-Old Cicada Larva 170,000-Year-Old Cicada Adult Armored GorillaAwakened Cockroach Baquma Beast King Bruinado Bug God Building Booper Deep Sea King Demonic Fan Devil Long Hair *Do-S *Eyesight Face Ripper Fist Fight Djinn Free Hugger G4 G5 Game-Berus Giant Crow Grizzly Nyah Hundred-Eyes Octopus Jumping Spider Macho Daikon Mosquito Girl Rafflesidon Rhino Wrestler Royal Ripper Scaledon Senior Centipede Showerhead Sky King Subterranean King Super Mouse Surprise-Attack Plum The Great Food Tub The Three Crows Unihorn Vampire (Pureblood) 
Wolf Himawari Hotdog Messenger of the Seafolk Piggy Bancon Tongue Stretcher
Less than Wolf
Unknown Alien Seer *Ancient King Angry Grandpa Autumn Phantom Red Golden-ringed Dragonfly *Benpatsu *Choze DarkDark Matter Gunner Eagle Enamel Evil Eggs Evil Eye Evil Natural Water *Falcon Fish of DarknessGale Giant Salamander Gigakigan Goddess Glasses Gyoffrey Hamukichi *Haragiri Hawk Hellfire Junior Centipede Kite Lord Great White ManakoMen's Esthetician Man *Platinum Sperm Rosie Raptora *RepteraSage Centipede Suppon Sword Devil Executioner Venus Mantrap Volten *