Jack Corbett

Billy 5000 (voice)

Grace Kuhlenschmidt

Freckles (voice)

Elsie Fisher

Beatbox (voice)

Janeane Garofalo

Dr. Dolphin (voice)

Miya Folick

Rosario 'Rozebud' Dolphin (voice)

Tavi Gevinson

Glarba (voice)

Julio Torres

T-Bone / Gas Station Guy / Brontosaurus (voice)

Sarah Sherman

Miss Sharon / Minivan Mom (voice)

Chris Fleming

Weenie (voice)

Cole Escola

Ol' Slippy / Nan (voice)

Joe Pera

Herschel Cretaceous (voice)

River L. Ramirez

Gordon Spaghetti / Fettuccini Enthusiast / Paramedic / Miniv

Demi Adejuyigbe

Mr. Moolah (voice)

Eva Victor

Gail 5000 (voice)

Max Wittert

Byron (voice)

J.R. Phillips

Peanut (voice)