Tom Kenny
Ice King (voice) (280 eps)
John DiMaggio
Jake the Dog (voice) (280 eps)
Pendleton Ward
Lumpy Space Princess (voice) (279 eps)
Olivia Olson
Marceline the Vampire Queen (voice) (279 eps)
Jeremy Shada
Finn the Human (voice) (279 eps)
Hynden Walch
Princess Bubblegum (voice) (279 eps)
Niki Yang
BMO / Lady Rainicorn (voice) (279 eps)
Polly Lou Livingston
Tree Trunks (voice) (279 eps)
Justin Roiland
Earl of Lemongrab (voice) (8 eps)
Ava Acres
Young Marceline (voice) (7 eps)
Kumail Nanjiani
Prismo (voice) (6 eps)
Emo Philips
Cuber (voice) (5 eps)
Ashly Burch
Breezy (voice) (5 eps)
Madeleine Martin
Fionna (4 eps)
Roz Ryan
Cake (4 eps)
Kristen Schaal
Jake Jr (voice) (4 eps)
Dan Mintz
Tv (voice) (4 eps)
'Weird Al' Yankovic
Banana Man (3 eps)
Andy Milonakis
Neptr (3 eps)
Andy Samberg
Party Pat / Rap Bear (3 eps)
Neil Patrick Harris
Prince Gumball (3 eps)
Mark Hamill
Dark Magician (voice) (3 eps)
M. Emmet Walsh
Cosmic Owl (3 eps)
Lou Ferrigno
Billy (3 eps)
Kent Osborne
Bounce House Princess (3 eps)
Henry Rollins
Bob Rainicorn (3 eps)
Steve Little
Abracadaniel (voice) (3 eps)
Lauren Lapkus
Patience St. Pim (voice) (3 eps)
Kyla Rae Kowalewski
Me-Mow (2 eps)
Kevin Michael Richardson
The Storm (2 eps)
James Urbaniak
Rat King / Leaf Beard (2 eps)
Thurop Van Orman
Tree Witch (2 eps)
George Takei
Ricardio (2 eps)
Donald Glover
Marshall Lee (2 eps)
Grey DeLisle
Ice Queen (2 eps)
Ako Castuera
Canyon (2 eps)
Laura Silverman
Ethel Rainicorn (2 eps)
John Hodgman
Elder Plops (2 eps)
Kate Micucci
Wendy (2 eps)
Riki Lindhome
Island Lady (voice) (2 eps)
Sharon Horgan
Minerva (voice) (2 eps)
Jenny Slate
Huntress Wizard (voice) (2 eps)
Jackie Buscarino
Eclair Boy (voice) (2 eps)
Felicia Day
Betty (voice) (2 eps)
Keith David
Balthus (voice) (2 eps)
Maurice LaMarche
Wizard Police (voice) (2 eps)
Alan Tudyk
Chatsberry (voice) (2 eps)
Paul Reubens
Gnome Ruler/Dancing Bug (voice) (1 eps)
Billy West
Goose / Erik Adamkinson / Mayor (voice) (1 eps)
Brian Doyle-Murray
Prince Huge (1 eps)
Alan Oppenheimer
Darren the Ancient Sleeper/Sun (voice) (1 eps)
Beau Billingslea
The Moon (voice) (1 eps)
Eric Bauza
Buttersotch Butler (voice) (1 eps)
Willow Smith
Beth (voice) (1 eps)
Sean Giambrone
Shermy (voice) (1 eps)
Brian Baumgartner
Georgy / Private (1 eps)
Toby Huss
Booboo / Commander (1 eps)
David Ferguson
Lifeguard (1 eps)
Hannibal Buress
Flame Prince (1 eps)
Crispin Freeman
Turtle Prince (1 eps)
Peter Serafinowicz
Lumpy Space Prince (1 eps)
Elle Newlands
Butterscotch Butler (1 eps)
Matthew Broderick
Dream Warrior (1 eps)
Bert Youn
Lee (1 eps)
Fred Stoller
Roy (1 eps)
Donald Faison
Princess Cookie (1 eps)
Kay Lenz
Bird Woman (1 eps)
Dee Bradley Baker
Mr. Cream Puff / Mr. Cupcake / Chet (voice) (1 eps)
Maria Bamford
Manfried / Chocoberry / Candy Corn Girl (voice) (1 eps)
Mark Proksch
Johnnie (1 eps)
Marc Maron
Squirrel (1 eps)
LeVar Burton
Bubble (voice) (1 eps)
Melissa Villaseñor
Clerk (voice) (1 eps)
Lucy Lawless
General Tarsal (voice) (1 eps)
Alia Shawkat
Betsy (voice) (1 eps)
Chelsea Peretti
Queen of Ooo (voice) (1 eps)
Paul Scheer
Toronto (voice) (1 eps)
Dave Foley
Warren Ampersand (voice) (1 eps)
James Baxter
James Baxter (1 eps)
J.G. Quintel
Blue Jay (voice) (1 eps)
John Moschitta Jr.
Key-per (voice) (1 eps)
Sam Marin
Gareth / Flying Lettuce Brother (voice) (1 eps)
Collin Dean
Tiffany (voice) (1 eps)
Cole Sanchez
Party God (voice) (1 eps)
Steve Agee
Ash (voice) (1 eps)
Martin Olson
Hunson Abadeer (voice) (1 eps)
Pamela Adlon
Gunther (voice) (1 eps)
Creed Bratton
Phlannel Boxingday (voice) (1 eps)
Open Mike Eagle
Gingerbread Rapper / Rapper Chipmunk (voice) (1 eps)
Stephen Root
Martin (voice) (1 eps)
Laraine Newman
Widow / Additional Voices (voice) (1 eps)
Lennon Parham
Additional Voices (voice) (1 eps)
Steve Wolfhard
Slimy D (voice) (1 eps)