The Grim Adventures of Billy & Mandy/Trivia
- Hey, It's That Voice! -
- Richard Horvitz as Billy and Harold
- David Warner as Nergal
- Grey De Lisle as Mandy
- Greg Eagles as Grim, using his Captain Bob voice.
- Diedrich Bader as Hoss Delgado.
- Don't forget Weird Al as the Squid Hat (and the announcer for the video game adaptation)!
- Dean Toadblatt's voice actor is Dean Wormer.
- Nergal Jr. is Jimmy Neutron.
- Jennifer Hale is Billy's mom
- Rachael MacFarlane is Mindy and Eris
- And who could forget Good Ole' Voltaire?
- Jack O'Lantern is Zurg.
- The Wiki Rule: The Grim Adventures of Billy and Mandy Wiki
- Word of God: Maxwell Atoms revealed that Grim, Mandy and Billy represent aspects of autistic people such as Atoms.