Goddard (voice) / Poultra (voice)
Frank Welker
Carl Wheezer (voice) / Mr. Wheezer (voice) / Mrs. Wheezer (voice) / Kid in Classroom (voice)
Rob Paulsen
Cindy Vortex (voice)
Carolyn Lawrence
Libby Folfax (voice)
Crystal Scales
Nick Dean (voice) / Britney (voice) / PJ (voice)
Candi Milo
Yokian Guard (voice) / Gus (voice)
David L. Lander
Mr. Estevez (voice)
Carlos Alazraqui
Ultra Lord (voice) / Mission Control (voice) / General Bob (voice)
Jim Cummings
Bobby (voice) / Kid (voice) / Control Yokian (voice)
Keith Alcorn
Zachary (voice) / Reporter (voice) / Angie (voice) / Libby's Mom (voice)
Kimberly Brooks
Ms. Winfred Fowl (voice)
Andrea Martin
Bobby's Twin Brother (voice) / Butch (voice) / Jailbreak Cop (voice) / Old Man Johnson (voice) / Robobarber (voice) / Flurp Announcer (voice) / Yokian Officer (voice) / Anchor Boy (voice) / Guard (voice)
Billy West