He is voiced by Rainn Wilson.
Peace Master is shown to hate the dark arts, but also loves his family. His love then turns into protection as he fights off Peppermint Butler. He is also shown to have a sense of humility as he is embarrassed during his battle.
He first appears is "Nemesis" where he attends of meeting to warn some Candy Kingdom citizens about a dark entity in Ooo. He claims that he hates evil then leaves and drives a van with his three kids (whom he has troubles with), after getting into a crash after the youngest one barfs all over the windshield he starts blaming the dark arts and starts kicking the van repeatedly.
He then fights off Peppermint Butler who has gotten armor from another dimension. During the fight Peppermint Butler demands that Peace Master hand over his charm stick. When he refuses Peppermint Butler turns two of his kids into a lizard and a flying fairly. Peace Master then throws the charm stick into a hole. After Peace Master does a few humiliating things, Peppermint Butler realizes that he's gone to far and lets him go and Peace Master then leaves with his kids.
Peace Master appears again in "Gumbaldia" as one of the many villains joining Uncle Gumbald's legion of Candy Kingdom haters to go to war with the Candy Kingdom.
In "Come Along With Me" he witnesses the arrival of GOLB then runs away with the rest of Gumbald's army after Aunt Lolly asks them to help her fight GOLB.
- Peace Master and his children seem to be the same species as Ron James, as they have the same skin color, head shape, and neck size as him.
- He bears a resemblance to Cad Bane from Star Wars: The Clone Wars.
- Coincidentally, in the Brazilian Portuguese version of Adventure Time, both Peace Master and Cad Bane are voiced by the same voice actor.
- The license plate on Peace Master's car spells "MIR" which means "peace" in Slavic languages.