- Alternate Character Interpretation: Velma is here pretty much the only one going against the grain still maintains her skepticism. Is she the Only Sane Man in this movie or just in blatant denial with cynicism her only defense mechanism?
- Author's Saving Throw:
- Flim Flam is aged up, probably because his status as a young kid contributed to his The Scrappy status.
- Daphne's appearance looks a lot more like her and in-character with her fashionista tendencies, as a complaint for The 13 Ghosts was that her character design looked too unrecognizable to be the same Daphne that we've often seen.
- The very creation of this film is pretty much making up for the fact that The 13 Ghosts of Scooby-Doo itself was Left Hanging for a very long time.
- Broken Base:
- Word of God confirming that the movie canonically takes place after Scooby-Doo on Zombie Island has been taken as this. On one hand, it confirms there's a Shared Universe between the newer animated movies, the first four animated movies, and the pre-A Pup Named Scooby-Doo shows. Plus, most people can justify any continuity snarls with the idea of Hanna Barbera continuity and the floating timeline note . On the other hand, it doesn't fit considering the number of Continuity Snarls it would entail, including the implication that the Gang returned to status quo despite the first four movies being about them as adults, and think that even with Hanna Barbera continuity, this is a stretch..
- This film's writing of Velma also seems to have caused a split even more so than the info from Word of God intended. As it seems clear the film did aim to end with two scenarios in terms of explanations (even if the writer slipped in an open interpretation to one) but in reality obviously only one can still be accurate. But this has resulted in some fans just taking Velma as the annoying character who everyone else didn't share opinions with and the others now assuming through Velma WB has retconned the entirety of The 13 Ghosts of Scooby-Doo into being All Just a Dream.
- Fanfic Fuel:
- Flim Flam somehow developed his own monster hunting shop somewhere between the end of 13 Ghosts and now.
- Scrappy is nowhere to be found in the film; what would've happened if he actually was in it?
- What would've happened if Velma did open the Chest of Demons?
- Harsher in Hindsight: The Adaptation Expansion of this movie adds that the ones responsible for putting the demons away the second time were just Vincent Van Ghoul and Mortifer. This makes the demons action of cursing the whole town as werewolves look rather cruel. But these being demons that isn't entirely out of character but the villagers who tell this story to the gang just said "many years ago the townsfolk..." so they themselves may actually not even know for sure and are just assuming because they were cursed their ancestors must have done it or worse Vincent lied to them over it.
- Hilarious in Hindsight:
- In Scooby-Doo! Mystery Incorporated, Fred and Daphne remark on a statue of Flim Flam that Fred was at camp when Flim Flam joined Mystery Incorporated and he ended up getting incarcerated for twenty-five years for a huge scam he did. They also see a statue of Scrappy, with Fred bringing up that they promised never to talk about him again. Come this movie and Flim Flam is aged up, Velma apparently doesn't know who Scrappy is when Flim Flam brings him up, and it's also explained that Fred and Velma were away at camp during the events of The 13 Ghosts.
- The crossover episode with Supernatural was released seven months before the announcement of the movie came out, and a large part of the episode was that the Gang couldn't handle the revelation that ghosts are real, so the Supernatural cast decided to lie to them that ghosts are still fake. Well... looks like that facade lasted a lot shorter than we expected.
- "Holy Shit!" Quotient: Double notion on two different sides of the fanbase. People who regard The 13 Ghosts of Scooby-Doo as a show either largely forgotten/unknown or known as being So Bad, It's Good would at long last be receiving a Fully Absorbed Finale via the DTV series as a total surprise. On the other when a leak was found a Scooby movie had the title "Curse of the 13th Ghost" there was some mild speculation it could be this only for a few days later much excitement/rejoicing when it turned out to be exactly what they had been expecting.
- Rescued from the Scrappy Heap: Flim Flam is probably one of the few characters in the franchise who was an even worse scrappy than the Trope Namer himself. In the movie, he's revealed to no longer be a hustler and has a legitimate business, sold his products to his close friends (without swindling) and his voice actor was pretty well received over all.
- Take That, Scrappy!: Scrappy-Doo for the most part has been left out of the film, but he did get a reference which Velma seems to deny knowing him. It isn't clear whether we are supposed to take this as a direct Take That!, a sign that we are supposed to understand Velma isn't to be taken seriously or just as a meta-joke that he's not here (something 13 Ghosts did a lot of). The later reveal by Word of God that Tim Sheridan did try to work Scrappy into the script may imply it's more likely the second or third rather than the first.
- They Changed It, Now It Sucks!:
- Some hardcore 13 Ghosts of Scooby-Doo fans aren't going to take some of the changes here that well which really should have been expected, not helped with the below mentioned Wasted Character for Scrappy.
- The explicit supernatural trappings of The 13 Ghosts being given the Maybe Magic, Maybe Mundane treatment. Especially since there have been blatant supernatural beings in the franchise before — the first four movies, the live-action films, and Mystery Incorporated, so there's really no need for it; what makes it more egregious is Vincent's crystal is explicitly supernatural (not even Velma can explain that one away) so making the nature of the Chest and its contents ambiguous is pretty much pointless other than making Velma's character annoying.
- Tim Sheridan confirming that the newer movies are canon with the first four movies (Zombie Island, The Witch's Ghost, The Alien Invaders, and The Cyber Chase), in spite of how many retcons this would have to do in order to make it work, especially how it ignores the well-liked concept of the Gang being adults and instead keeps them as teenagers.
- They Wasted a Perfectly Good Character: Some fans are disappointed that Scrappy-Doo doesn't have any involvement in the film aside from being briefly mentioned by Flim Flam, when the film could've, as was done with Flim Flam, taken the opportunity to have Scrappy Rescued from the Scrappy Heap.
- They Wasted a Perfectly Good Plot: Maybe not as harsh as that, but to make a movie sequel to a series with an unfinished story and then end this movie with a Maybe Magic, Maybe Mundane ending that in itself might not be conclusive just reeks of confusion. Unless mind you this isn't the last we see of some of these plot elements.
- Unexpected Character: While the movie largely came out of left field, the fact that Flim-Flam, a character very much hated by the fanbase (and to the point even the showrunner, Tom Ruegger, hated him) is in the movie was very surprising.
YMMV / Scooby-Doo! and the Curse of the 13th Ghost