Charlie Adler (38)

Ickis (voice)

Andrea Martin (47)

Gromble's Mom (voice)

Christine Cavanaugh (31)

Oblina (voice)

David Eccles (29)

Krumm / Snorch (voice)

Gregg Berger (43)

The Gromble (voice)

Jim Belushi (40)

Simon the Monster Hunter (voice)

Kath Soucie (33)

Blorp 2+4 / Woman (voice)

Lacey Chabert (12)

Girl (voice)

Michael Dorn (41)

Borl / Chauffer (voice)

Bronson Pinchot (35)

Deitrich Dunlap (voice)

Tim Curry (48)

Zimbo (voice)

Shelley Duvall (45)

Ocka (voice)

Beverly Archer (46)

The Library Monster (voice)

Edward Winter (57)

Dr. Buzz Kutt (voice)

Billy Vera (50)

Slickis (voice)

Marcia Strassman (46)

Harryette (voice)

Bill Fagerbakke (37)

Carl (voice)

Susan Blu (46)

Mom / Hair / Kid 4 (voice)

Aaron Michael Metchik (14)

Kid 3 / Kid 6 (voice)

Erik von Detten (12)

Vic / Tough Kid (voice)

Jarrett Lennon (12)

Kid 1 (voice)

George Segal (60)

J.B. (voice)

Ian Ziering (30)

Gludge (voice)

Bruce Weitz (51)

Luxor (voice)

Fyvush Finkel (72)

Jackie the Shtickman (voice)

Brock Peters (67)

The Pool (voice) / Snorch's Voicebox (voice)

Sven-Ole Thorsen (50)

Lars Halverson (voice)

Gary Owens (60)

Unknown

Arthur Burghardt (47)

Elban Bigfoot (voice)

Taj Mahal (52)

Ellis Robinson (voice)