 James UrbaniakDr. Venture / Phantom Limb / Jonas Venture Jr. (voice) | Dr. Venture / Phantom Limb / Jonas Venture Jr. (voice) |
 Patrick WarburtonBrock Samson (voice) | Brock Samson (voice) |
 Michael SinterniklaasDean Venture (voice) | Dean Venture (voice) |
 Doc HammerDr. Mrs. The Monarch / Henchman 21 / Shoreleave / Billy Quizboy / Dermott / Red Mantle / Rose / Ward (voice) | Dr. Mrs. The Monarch / Henchman 21 / Shoreleave / Billy Quizboy / Dermott / Red Mantle / Rose / Ward (voice) |
 Christopher McCullochHank Venture / The Monarch / Sgt. Hatred / Hunter Gathers / Pete White / Watch (voice) | Hank Venture / The Monarch / Sgt. Hatred / Hunter Gathers / Pete White / Watch (voice) |
 Nina AriandaMantilla (voice) | Mantilla (voice) |
 Clancy BrownRed Death / Daisy (voice) | Red Death / Daisy (voice) |
 John HodgmanSnoopy (voice) | Snoopy (voice) |
 Hal LublinClayton / Seth / Tour Guide (voice) | Clayton / Seth / Tour Guide (voice) |
 Jane LynchBobbi St. Simone (voice) | Bobbi St. Simone (voice) |
 Charles ParnellJefferson Twilight / OSI Agent (voice) | Jefferson Twilight / OSI Agent (voice) |
 Jay PharoahNuno Blood / Additional Blackulas (voice) | Nuno Blood / Additional Blackulas (voice) |
 Steven RattazziDr. Orpheus (voice) | Dr. Orpheus (voice) |
 J.K. SimmonsBen (voice) | Ben (voice) |
 Dana SnyderThe Alchemist / Conductor / Houseless Guy (voice) | The Alchemist / Conductor / Houseless Guy (voice) |
