1,164 Pages

Angry Grandpa (マジギレ, Majigare) was a mysterious being that appeared in the audio book, "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 never 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.


Audio BooksEdit

Sonic, Becoming SaitamaEdit

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

Abilities and PowersEdit

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

Physical AbilitiesEdit

Enhanced Strength: Angry Grandpa was strong enough to punch holes in the ground.[2]

Enhanced Durability: Angry Grandpa could withstand bullets to no apparent damage.[3]

Frustration Accumulation: As Angry Grandpa accumulated frustration, he could unleash bursts of immense power.[4]

Fighting StyleEdit

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

  • Furious Outburst Punch: The punch was strong enough to destroy concrete.[5]

Trivia Edit


  1. Audio_Books/Maji_Drama_CD_Vol._3
  2. One-Punch Man Audio Book; Sonic, Becoming Saitama
  3. One-Punch Man Audio Book; Sonic, Becoming Saitama
  4. One-Punch Man Audio Book; Sonic, Becoming Saitama
  5. One-Punch Man Audio Book; Sonic, Becoming Saitama


Mysterious Beings
Unaffiliated Crablante Vaccine Man Marugori Subterranean King  (Subterranean People) • Kombu Infinity170,000-Year Magicicada Nymph 170,000-Year Magicicada Adult Demonic Fan Pesky ClownPiggy Bancon Deep Sea King  (Seafolk) • Personification Of A Light Pull CordSurprise-Attack Plum Grizzly NyahSky King  (Skyfolk) • Game-Berus Octopus Claw Man Suppon Giant Crow Tongue StretcherEagle Hawk Falcon Kite Lord Great White Jumping Spider Giant Snowman Himaaku Hotdog GigakiganDeloreanThree Eyed Ghost Scaledon Enamel Pot Bellee Man-Eating Capybara Twin-Headed Tsuchinoko Kenzan Rat Forest King  (Forest Tribe) • Withered Sprout Macho Daikon Black Roast Alien SeerAutumn Phantom Red Golden-ringed Dragonfly
Dark Matter Thieves Boros Geryuganshoop Melzargard Groribas Dark Matter Gunner 
The Organization G4 G5 
House of Evolution Carnage Kabuto Beast King Armored GorillaKamakyuri Ground Dragon Frog Man Slugerous Mosquito Girl 
Anime-Only Mysterious Beings Super Custom YO649Z Mk. II Ancient King  (Terror Lizard Clan) • Fish of DarknessPluton Men's Esthetician Man *
Community content is available under CC-BY-SA unless otherwise noted.