Richard Steven Horvitz

Billy / Billybot / Harold / Pale Ghoulish Juror / Chippy the Squirrel (voice) (as Richard Horvitz)

Grey DeLisle

Mandy / Mandroid / Older Mandy / Milkshakes / Some Kid (voice)

Greg Eagles

Grim / Sperg / Pirate #6

Vanessa Marshall

Irwin / Pirate #5 / Unicorn (voice)

Maxwell Atoms

I'll Cut You Guy / Pirate #2 / Horrorbot / Burnt Skeleton Guard (voice)

Jane Carr

Bride of Frankenstein (voice)

Greg Ellis

Creeper / Horror's Hand / Pirate #3 / Paperboy (voice)

C.H. Greenblatt

Fred Fredburger / Pirate #4 (voice)

Jennifer Hale

Billy's Mom (voice)

Dorian Harewood

Older Irwin (voice)

Phil LaMarr

Space Villain / Glacier of Evil / Dracula / Judge Roy Spleen / Underworld Cop (voice)

Rachael MacFarlane

2 Headed Parrot (voice)

George Segal

Horror (voice)

Armin Shimerman

General Skarr / Pirate #7 (voice)

Lauren Tom

Numbuh Three (voice)

Billy West

Pirate #8 / Miniature Cyclops / Spider Clown Mailman / Beast Master (voice)

Fred Willard

The Boogey Man (voice)