Pendleton Ward
Lumpy Space Princess (voice) (26 eps)
Olivia Olson
Marceline the Vampire Queen (voice) (26 eps)
Jeremy Shada
Finn the Human (voice) (26 eps)
John DiMaggio
Jake the Dog (voice) (26 eps)
Tom Kenny
Ice King (voice) (26 eps)
Hynden Walch
Princess Bubblegum (voice) (26 eps)
Niki Yang
BMO / Lady Rainicorn (voice) (26 eps)
Polly Lou Livingston
Tree Trunks (voice) (26 eps)
Ava Acres
Sunshine / Jamaica (voice) (2 eps)
Kyla Rae Kowalewski
Me-Mow (1 eps)
Kevin Michael Richardson
The Storm (1 eps)
'Weird Al' Yankovic
Banana Man (1 eps)
James Urbaniak
Vice President Blowfish (1 eps)
Ako Castuera
Canyon (1 eps)
Kumail Nanjiani
Prismo (voice) (1 eps)