Guest Stars Jeff Bennett voices Choose Goose Hynden Walch voices Princess Bubblegum Steve Little voices Peppermint Butler Tom Kenny voices Berdzerd Dana Snyder voices Life Giving Magus Dana Snyder voices Potable Wizard Maurice LaMarche voices Skull Maurice LaMarche voices Wizard Cop #1 Edi Patterson voices Momdebra Edi Patterson voices Cat Student Julia Butters voices Larry Bex Taylor-Klaus voices Blaine Anthony Stewart Head voices Con Wizard Bill Hader voices Bufo Toks Olagundoye voices Dr. Caledonius Chloe Coleman voices Cadebra Steve Little voices Abracadaniel Duncan Trussell voices Ron James Patti Harrison voices Weapon Head SungWon Cho voices Wizard Cop #2 John Omohundro voices Spader SungWon Cho voices Brain Wizard Sheng Wang voices Dimension Wizard Cole Sanchez voices Little Dude Co Starring John DiMaggio voices Additional Voices Tom Kenny voices Additional Voices Pendleton Ward voices Additional Voices Jeremy Shada voices Additional Voices Niki Hyun Yang voices Additional Voices Cole Sanchez voices Additional Voices Jeff Bennett voices Additional Voices Julia Butters voices Additional Voices Bex Taylor-Klaus voices Additional Voices SungWon Cho voices Additional Voices