Charlie Adler

Ickis (voice)

Christine Cavanaugh

Oblina (voice)

David Eccles

Krumm / Snorch (voice)

Gregg Berger

The Gromble (voice)

Jim Belushi

Simon the Monster Hunter (voice)

Kath Soucie

Blorp 2+4 / Woman (voice)

Lacey Chabert

Girl (voice)

Michael Dorn

Borl / Chauffer (voice)

Bronson Pinchot

Deitrich Dunlap (voice)

Tim Curry

Zimbo (voice)

Shelley Duvall

Ocka (voice)

Beverly Archer

The Library Monster (voice)

Edward Winter

Dr. Buzz Kutt (voice)

Billy Vera

Slickis (voice)

Marcia Strassman

Harryette (voice)

Bill Fagerbakke

Carl (voice)

Susan Blu

Mom / Hair / Kid 4 (voice)

Aaron Michael Metchik

Kid 3 / Kid 6 (voice)

Erik von Detten

Vic / Tough Kid (voice)

Jarrett Lennon

Kid 1 (voice)

George Segal

J.B. (voice)

Andrea Martin

Gromble's Mom (voice)

Ian Ziering

Gludge (voice)

Bruce Weitz

Luxor (voice)

Fyvush Finkel

Jackie the Shtickman (voice)

Brock Peters

The Pool (voice)

Sven-Ole Thorsen

Lars Halverson (voice)

Gary Owens

Acteur

Arthur Burghardt

Elban Bigfoot (voice)

Taj Mahal

Ellis Robinson (voice)

John Pankow

Blook the Granfaloon (voice)

William Hootkins

Loch Ness Monster (voice)

Keith Szarabajka

Skritch (voice)

Mark DeCarlo

Pitch Monster (voice)

Stuart Whitman

Mule Morgan (voice)

Norbert Weisser

Farfegnuton (voice)

Jason Graae

Z-12 (voice)

David Workman

X-14 (voice)

Mitzi McCall

Custodian Monster (voice)

Peter Bonerz

Sal (voice)

Conchata Ferrell

Simpah (voice)

John Rhys-Davies

Head Judge / Zifdo (voice)

Mayim Bialik

Acteur

Jonathan Winters

Acteur

Cynthia Mann

Dizzle (voice)

Kevin Michael Richardson

Clem Lashinsky / Zooeuh (voice)

Kevin McBride

Car Wash Man / Skater #1 (voice)

Candi Milo

Splazu / Skater #2 (voice)