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)
George Ball
Peequay (voice)
Jane Carr
Bride of Frankenstein (voice)
Greg Ellis
Creeper / Horror's Hand / Pirate #3 / Paperboy (voice)
Bart Flynn
Giant Cyclops / Ugly Pirate (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)
James Silverman
Executioner / Pirate #1 (voice)
Lauren Tom
Numbuh Three (voice)
Billy West
Pirate #8 / Miniature Cyclops / Spider Clown Mailman / Beast Master (voice)
Fred Willard
The Boogey Man (voice)