Fionna

Madeleine Martin

Cake

Roz Ryan

Simon Petrikov

Tom Kenny

Gary Prince

Andrew Rannells

Additional Voices (voice) / The Heart of the Forest / Za'Baby (voice)

Dee Bradley Baker

Marshall Lee (voice) / Marshall Lee / Monster Marshall (voice)

Donald Glover

Scarab (voice) / Scarab / Miss Rabow (voice)

Kayleigh McKee

Finn (voice) / Baby Finn (voice) / Babyworld Finn (voice)

Jeremy Shada

Prismo 1/Prismo 2/Prismo 3

Sean Rohani

Ellis P / Norm (voice) / Alien Robot (voice)

Pendleton Ward

Astrid (voice) / Young Marceline / Astrid

Audrey Bennett

Jake

John DiMaggio

Queenie (voice) / Frozen Turkey (voice)

Chelsea Peretti

Princess Bubblegum (voice) / Princess Bubblegum / Passing Child (voice)

Hynden Walch

Huntress Wizard (voice)

Ashly Burch

Gary (voice)

Harvey Guillén

Hunter (voice) / Hunter / Fern (voice)

Vico Ortiz

Slime Princess / Finn's Kid #1 (voice) / Starchy (voice)

Maria Bamford

Marceline (voice) / Marceline / Celine (voice)

Olivia Olson

Marshall Lee (voice)

Kris Kollins

Lemoncarb #1 (voice) / Additional Voices (voice) / Lemoncarb #1

Jinkx Monsoon

DJ Flame (voice) / DJ Flame / Flame Prince (voice)

Manny Jacinto

Hana Abadeer (voice)

Erica Luttrell

BMO (voice) / Additional Voices (voice) / BMO

Niki Yang

Additional Voices (voice) / Lemoncarb #2 (voice) / Lemoncarb #2

Cree Summer

Simone (voice) / Ice Queen / Muscle Princess

Grey DeLisle

Kheirosiphon / Wyatt (voice) / Cliff (voice)

Andy Daly

Spirit Dream Warrior (voice)

Matthew Broderick

Additional Voices (voice) / Peptank (voice) / Sam

Steve Little

Party God / Pickle Reviewer #1 (voice) / Person 1 (voice)

Cole Sanchez

Fennel / MG (voice) / Person 2 (voice)

Anna Akana

Evil Choose Goose (voice) / Choose Bruce / Earmworld Dad (voice)

Jeff Bennett

Squirrel (voice) / Additional Voices (voice) / Squirrel

Marc Maron

Additional Voices (voice) / Ice Scout #1 (voice) / Skater Fairies (voice)

Erica Mendez

DJ Slime (voice) / DJ Slime / Clapper (voice)

Will Pendarvis

Additional Voices (voice) / Skater Fairies (voice) / Ice Scout #2 (voice)

Cristina Valenzuela

Betty (voice)

Felicia Day

Dog Cake / Nightmare Cake / Beard Guy (voice)

Phil LaMarr

Orbo (voice)

Dave McCormack

Pep (voice)

Mace Montgomery Miskel

Witch Wizard (voice)

Patti Harrison

Everplant / Little Destiny (voice) / Additional Voices (voice)

Mickey Zacchilli

Additional Voices (voice) / Minerva / Minervabot (voice)

Sharon Horgan

Prismo (voice)

Kumail Nanjiani

Tree Wizard (voice) / Nova (voice) / Tree Wizard

Rosie Brand

Cosmic Owl (voice) / Cosmic Owl / Brother #1 (voice)

Frank Collison

Young Marshall Lee (voice)

Rumi C. Jean-Louis

Marshmallow Kid (voice)

Open Mike Eagle

Damon (voice) / Damon / Dane (voice)

Kent Osborne

Blade Wizard / Narrator (voice) / Blade Wizard (voice)

Andy Merrill