Finn
Jeremy Shada
Jake
John DiMaggio
Ice King (voice) / Flying Lettuce Brother (voice)
Tom Kenny
Princess Bubblegum
Hynden Walch
Lumpy Space Princess (voice)
Pendleton Ward
BMO / Lady Rainicorn (voice)
Niki Yang
Tree Trunks (voice)
Polly Lou Livingston
Goliad
Wendy Linehan
Princess Cookie
Donald Faison
Flame Princess
Jessica DiCicco
Marceline
Olivia Olson
Dream Warrior
Matthew Broderick
The Elder
Jonathan Katz
Barb
Susie Essman
King Worm
Erik Estrada
Stormo
Henry Linehan
N.E.P.T.R./Dream BMO
Andy Milonakis
Ricardio
George Takei
The Farm
Tom Gammill
Hunson Abadeer/Evil Marceline/Demon
Martin Olson
The Bear/Candy Person
Eric Bauza
Death/Grod
Miguel Ferrer
Ed/Bird 1
Bobcat Goldthwait
Immortal Maize Walker
Gregg Turkington
Prince Huge
Brian Doyle-Murray
Mr. Cupcake
Dee Bradley Baker
Candy Nanny
Jill Talley
Charlic's Dad/Demon
Steve Agee
The Train
Dana Snyder
The Lich
Ron Perlman
Marauders
Kent Osborne
Billy
Lou Ferrigno
Torcho/Flame Soldier 2/Flame Citizen
Maria Bamford
Mr. Pig
Ron Lynch
Earl of Lemongrab (voice) / Lemongrab 2 (voice) / Starfish Martian (voice)
Justin Roiland
Grob
Melissa Villaseñor
Dementor
Bryan Kopta
Finn's Mom
Ming-Na
Peppermint Butler
Steve Little
Marauders
Cole Sanchez
Cuber (voice)
Emo Philips
Young Marceline (voice) / Candy Kids (voice) / Jamaica (voice)
Ava Acres
Flame King
Keith David
Toughy/Blombo
Max Charles
Polly Lou Livingston
Furnius/Jalapeño Pepper/Flame Soldier 3
Paul F. Tompkins
Prismo (voice)
Kumail Nanjiani
Cole Sanchez
Breezy (voice) / Blacksmith / Scorpion (voice)
Ashly Burch
Fionna
Madeleine Martin
Cake
Roz Ryan
Jake Jr (voice) / Jack Jr (voice)
Kristen Schaal
Tv (voice)
Dan Mintz
Banana Man
'Weird Al' Yankovic
Party Pat / Rap Bear / Party Splat
Andy Samberg
Prince Gumball
Neil Patrick Harris