Guest appearances in other Hanna-Barbera and Warner Bros. productions

The following is a list of official guest appearances (whether canon or not) in other productions produced by Hanna-Barbera and later Warner Bros. Animation

Looney Tunes: Back in Action

 * Shaggy Rogers and Scooby-Doo (voiced by Casey Kasem & Frank Welker, respectively) make cameo appearances, talking to Matthew Lillard about how he portrayed Shaggy in . Shaggy told Lillard he made him sound like a space cadet and warned if he goofed on him in the sequel, he would come after him and Scooby said he'd give him a Scooby Snack.

Duck Dodgers

 * During a montage in Surf the Stars, featuring Brian Wilson's song "Believe in Yourself", Mystery Inc., followed by Scooby-Doo, Where Are You! monsters (including Ghost of Captain Cutler, Ghost of Redbeard, the witch, Creeper, and the Green Ghost), all run past the screen.

Dynomutt, Dog Wonder

 * The series premiered alongside The Scooby-Doo Show in 1976. To capitalize on this, Mystery Inc. gang guest starred in Everyone Hyde!, What Now, Lowbrow?, and The Wizard of Ooze. The main cast reprised their roles, which were Don Messick, Kasem, Welker, Heather North, and.

Johnny Bravo

 * The gang were guest stars in Bravo Dooby-Doo. Welker, Kasem, and North reprised their roles as Fred, Shaggy, and Daphne, respectively. While new actors B.J. Ward and Hadley Kay were hired for Velma and Scooby, respectively. Kay then reprised the role for a Scooby cameo in  ' Twas the Night.

Harvey Birdman, Attorney at Law

 * The gang were guest stars in Shaggy Busted. The cast included Scott Innes as Scooby and Shaggy, Frank Welker as Fred, Grey DeLisle as Daphne, Ward as Velma, with a cameo from Scrappy-Doo, also voiced by Innes.

Batman: The Brave and the Bold

 * The gang are guests in a segment of Bat-Mite Presents: Batman's Strangest Cases!, in a parody of The New Scooby-Doo Movies. The cast included Welker as Scooby and Fred, Lillard as Shaggy, DeLisle as Daphne, and Mindy Cohn as Velma.

Sabrina the Teenage Witch (live-action)

 * In Sabrina Unplugged, when Sabrina is caught by the office webcam using her powers, she magically enters Leonard's computer to destroy the evidence and meets up with Shaggy and Scooby (voiced by Innes and Welker, respectively). He asks her if she can get them off as a screensaver, as they're embarrassed. Both shows aired on The WB at the time.

Supernatural

 * The gang are guests in Scoobynatural, when three of the main characters of Supernatural are sucked into the episode . The cast included Welker as Scooby and Fred, Lillard as Shaggy, Griffin (formerly DeLisle), and Kate Miccuci as Velma.

OK K.O.! Let's Be Heroes

 * In the episode Monster Party, the main students of Miss Grimwood's Finishing School for Ghouls in the TV film Scooby-Doo and the Ghoul School guest star. The cast for the girls include Pat Musick, Russi Taylor, Susan Blu, Kristen Li, Natalie Palamides as Elsa Frankenteen, Phantasma, Sibella, Tanis, and Winnie Werewolf, respectively.

Teen Titans Go!

 * The gang are guest stars in the episode Cartoon Feud. The cast is Welker as Scooby and Fred, Lillard as Shaggy, Griffin as Daphne, and Micucci as Velma.