Fred/Scooby

Frank Welker

Norville 'Shaggy' Rogers (voice)

Matthew Lillard

Velma

Mindy Cohn

Daphne Blake (voice)

Grey DeLisle

Angie Dinkley (voice) / Mrs. Dinkley (voice)

Frances Conroy

Doogle McGuiness/Blaine LeFranc

Jeff Bennett

Dr. Henklefust

John Billingsley

Nova

Amy Acker

Krod (voice) / Blue Falcon (voice) / Commercial Announcer (voice)

Troy Baker

Mary-Ann Geerdon

Isabella Acres

Professor Horatio Kharon

Michael J. Anderson

Kriegstaffebot (Voice) / Gene Shepherd (voice) / Headless Horror (voice)

Dee Bradley Baker

Krampus/Punk Kid

Carlos Alazraqui

Luna

Kimberly Brooks

Dr. Benton C. Quest/Old Clerk/Dr. Zin

Eric Bauza

Sheriff Bronson Stone (voice)

Patrick Warburton

Professor Enrique Andelusossa

Christian Lenz

Charles "Cachinga" Wheatlesby/Destroido Computer

Greg Ellis

Mr. E (voice) / Mr. E / Ricky Owens (voice)

Lewis Black

Ian Hope

Quinton Flynn

Dan Fluunk/Fiend

Kevin Michael Richardson

Evallo Von Meanskrieg

Chris Hardwick

Mayor Fred Jones Sr. (voice) / Mayor Fred Jones Sr. / Motorcycle Cop (voice)

Gary Cole

Granny Snaggletooth

Laraine Newman

Thorn

Jennifer Hale

Dad

David Kaye

Nibiru

Clancy Brown

Picnicker

Clyde Kusatsu

Fernando El Aguirre

Christian Lanz

Professor Pericles (voice)

Udo Kier

Melvin Keisterbaum

Phil LaMarr

Angel Dynamite (voice) / Cassidy Williams (voice)

Vivica A. Fox

Race Bannon/Bobo

Christopher Corey Smith

Crybaby Clown

Mark Hamill

Dandy Highwayman

James Marsters

Marcie 'Hot Dog Water' Fleach (voice) / Marcy 'Hot Dog Water' Fleach (voice) / Hot Dog Water (voice)

Linda Cardellini

Dr. Rick Spartan

James Patrick Stuart

Nan Blake

Kath Soucie

Frau Gluck

Mindy Sterling

Vincent Van Ghoul

Maurice La Marche

George Avocados (voice) / George Avocados / Rung Ladderton

James Arnold Taylor

Skipper Shelton

John O'Hurley

Brad Chiles (voice)

Tim Matheson

Judy Reeves (voice) / Amy (voice)

Tia Carrere

Herself

Martha Quinn

Randy Warsaw/Butch Firbanks

Billy West

Gluten Demon (voice) / The Phantom (voice) / Demon Dog (voice)

Fred Tatasciore

Baylor Hotner

Matt Lanter

Mayor Janet Nettles (voice) / Principal Quinlan (voice)

Kate Higgins

Ethan (voice) / Dylan (voice) / Farmer (voice)

Mitch Watson

Ned Fussbuster

Charles Shaughnessy

J.R. Kipple

Jim Rash

Horbert Feist

Jason Marsden

Himself

Harlan Ellison

Gorgeous G

Roz Ryan

Dusk

Jane Wiedlin

Arturo Mercado

Gary (voice) / Gary / Referee #2 (voice)

Tony Cervone

Colton Rogers (voice)

Casey Kasem