Mark Hamill will also reprise The Joker.You can't expect Mark Hamill to be in your show, then have a Batman episode where Kevin Conroy voices Batman and Joker is voiced by someone else like Troy Baker.
- It's more likely than you think. Justice League Action had a short where Mark Hamill gets kidnapped by the Joker and the Trickster, and Mark Hamill was also doing their voices for that show.
- Confirmed. He's the suspect in "What a Night for a Dark Knight", disguising himself as Man-Bat.
Place your guesses for other guest stars here.
- A contemporary rapper like Lil' Yachty or Kevin Gates.
- Stephen Merchant, Karl Pilkington or both, possibly in the same episode as Ricky Gervais. It would go a long way to dispel the rumors that the trio had fallen out.
- Jerry Seinfeld, possibly alongside Jason Alexander, Julia Louis-Dreyfus, and Michael Richards (either as themselves or reprising their famous roles from the TV show).
- The title character of Frasier, possibly alongside his friends and loved ones (except for Martin, because nobody will be able to replace John Mahoney.)
- The episodes featuring Batman, Flash, and Wonder Woman will also feature many prominent members of their respective rogues galleries.
- Teen Titans Go!. What? The Team-Up comics already did it! And it seems like something Warner Bros. and Cartoon Network would do again...
- Sabrina the Teenage Witch, especially since it's getting a reboot.
- Young Justice. The creators of Young Justice have tried pitching a crossover between both entities (one of the creators, Brandon Vietti, in fact, worked on some of the Scooby-Doo movies and got some of the Team's girls to cameo in the first WWE crossover movie), and Young Justice is coming back, so now's their chance.
- Archie or Riverdale. Maybe even Josie and the Pussycats.
- If they go with the comics' design, they could get Andrew Rannells to voice Archie.
- The return of the Ghoul School girls.
- OK KO did it.
- Special appearances by the G1 Transformers.
- Hasbro would never go for it.
- The Addams Family. It would be a nice opportunity to do another crossover with the Mystery Inc. gang and Addams Family again.
- Tom and Jerry, since they haven't met the Scooby-Doo gang in a crossover once.
- Markiplier, since he's a Let's Player most well known for playing Horror Games. They could even make the Monster of the Week for him and the gang to face Video Game-themed villains.
- Bonus points if they can get permission to include characters from Five Nights at Freddy's ...
- WWE wrestlers like John Cena. And members from the band, Kiss. I mean, Scooby-Doo DID do crossover movies with WWE and KISS, so even if they don't appear, a wrestler or rock musician appearing in the series isn't exactly out of the question.
- A time-travel episode featuring Doc Brown (voiced by Christopher Lloyd) and Marty McFly (voiced by Michael J. Fox) from the Back to the Future franchise.
- Characters from Steven Universe or OK K.O.! Let's Be Heroes. The former could play with expectations with whether the perpetrator of that episode's crimes is a Gem or a human in disguise, and the latter could make reference to K.O. and Enid's familiarity with the Ghoul School gals that Shaggy had met.
- Godzilla, from Hanna-Barbera's The Godzilla Power Hour. He could have either his classic cartoon green or his Scooby-Doo and the Ghoul School charcoal coloration.
- And hopefully this time, Toho will consent to him using his original roar (even if it's his MonsterVerse roar).
- Several real-life celebrities, like Ben Schwartz, Noel Wells, David Spade, Seth Rogen, Paget Brewster, Patton Oswalt, Josh Gad, Jack Black, Don Cheadle, Ed Asner, Billy Crystal, David Tennant, and Will Arnett.
- You know what crossover Im honestly shocked hasnt happened yet? GHOSTBUSTERS. (Potentially their animated incarnations). It would be fun to see the two groups working together and debating whether the mystery was because of real ghosts or fake ones, and you could have it be a compromise where the Monster of the Week is someone in a costume, but all the ghosts theyre commanding are the real deal via some kind of cursed artifact. Plus, a bunch of guys whose job is to GET RID of all the spooks and specters in the world? Scooby and Shaggy would worship the very ground they walk on.
There will be references to the previous Scooby-Doo shows/movies.
- Crystal Cove getting mentioned.
- Shaggy saying he had an alien girlfriend once.
- Fred mentioning that his dad is/was not a good person.
- Daphne has several sisters.
- Velma has a best friend outside of the gang.
- Fred had a terrible childhood friend.
- The Gang is friends with a high school classmate who is good with computers and video games.
- Daphne has an interest in journalism.
- Fred has an interest in literature and/or writing.
- Scooby's love life isn't going so well.
- The Gang has already teamed up with Batman and several other heroes in the past, specifically citing the crossover movie with Batman: The Brave and the Bold.
- Referencing "Scoobynatural", the Gang finds the notion of real zombies, witchcraft, ghosts, aliens, eldritch abominations, and so on, ridiculous.
- And Daphne will say at least once that "There are no such thing as ghosts!"
- Or they'll reference Scoobynatural itself, maybe with a vague mention of a trio of people that savvy viewers will recognize as Sam, Dean, and Cas.
- Confirmed, the entire gang meets Mudsy, a very real ghost, and are all convinced he's just the product of some really good special effects.
- It'll be mentioned that there are other mystery-solving groups, referencing the Scooby-Doo clones that Hanna-Barbera made and the predecessors in Mystery Incorporated.
- Daphne and Velma went to a different school together before they met Fred, Shaggy, and Scooby.
There will be something special for the franchise's 50th anniversary.
- Since 2019 celebrates 50 years of this franchise, it's highly plausible.
- Thanks, thats Exactly What It Says on the Tin.
There will be Take Thats towards Scrappy-Doo.
- Alternatively, if he does appear, they may rescue him from his own heap. Or...possibly even a mix of both.
- They managed to rescue Flim-Flam from the heap, so Scrappy shouldn't be too hard.
This takes place in the same universe as the '10 DTV movies.They already had a thing for celebrity guest stars. It makes sense if this trend is something unique-ish to this universe.
The show takes place in the reset universe at the end of Mystery Incorporated.
This takes place in the same universe as Justice League Action.Rachel Kimsey is reprising her role as Wonder Woman and Kevin Conroy also played as Batman in that version as well. Additionally, Wonder Woman's outfit and weapons are based on her depiction in Justice League Action.
The plot of the Gaffigan episode will involve bacon in some way.Either that or it will be rife with bacon jokes, since they can't afford the rights to advertise "Hooooooot Pocket" on the show.
- Jossed. The food-related humor involved burgers and fries due to taking place at a fast food joint.
Episodes will be dedicated to guest stars from The New Scooby-Doo Movies who are no longer with us.
The museum director in "When Urkel-bots Go Bad" is based off Carl Winslow.The guy is Carl Winslow as a museum director. He is overweight, has a mustache, is very short tempered, and is annoyed at Steve's antics. Also, it looks like he's wearing a police uniform underneath his coat, which could be a homage to Carl.
Most viewers expected Kel Mitchellto at least be mentioned in the episode featuring Kenan Thompson as a guest star.