- Actor Allusion: At one point, Velma laments that she suspected Crane of a "crime he didn't commit". Scarecrow in this movie is voiced by Dwight Schultz, probably best known for "Howling Mad" Murdock in The A-Team.
- Casting Gag: In the Mexican Spanish dub, Elvira is voiced by Yolanda Vidal who voiced Daphne from 2001-2015; so Daphne and Elvira's subplot also becomes a bit of a symbolic passing the torch onto her new voice actress Sandra Olarra.
- Completely Different Title: The film is listed on Digital eMation's website as "Scooby-Doo Halloween: Jack-o-pocaliypse!"
- Early-Bird Release: The DVD was released several weeks early on September 15 (and even earlier on the 14th in the UK), exclusively at Wal-Mart, before the general release on October 6.
- Executive Meddling: The theme of the movie, Elvira's presence, and the main villain were all mandated by the studio according to Maxwell Atoms.
- The Original Darrin: After all of Mystery Inc. (sans Scooby-Doo himself) were controversially Darrin'd in favor of celebrity voices in SCOOB!, this film sees the original voice cast reprise all their roles.
- The Other Darrin: Technically if we count Scooby-Doo! & Batman: The Brave and the Bold, Scarecrow's one line is provided by Dee Bradley Baker as per the original cartoon, but is voiced here by Dwight Schultz. Unintentionally continuing a franchise tradition of him not having the same voice actor even within the same continuity.
- Promoted Fanboy: Maxwell Atoms finally got the chance to work on one of his favorite franchises proper after giving the Scooby gang cameos on The Grim Adventures of Billy & Mandy and is for him complete vindication for when Cartoon Network Studios gave him grief for choosing to Shout-Out Hanna-Barbera properties.
- Release Date Change: According to Maxwell Atoms at 26:30, the movie would've been released in 2019 to coincide with the 50th anniversary, but because of the crunch time in making the movie, it was released in 2020.
- Role Reprise: In addition to most of the current Mexican Spanish dub cast for the Scooby gang, Scarecrow is voiced by Jesse Conde reprising his role from Batman: Arkham Knight and Injustice 2. This is in contrast to the original English, where he's voiced by a new actor altogether (because let's face it, Crane goes through voice actors like he does doctors at Arkham).
- Throw It In: Grey DeLisle Griffin improvised the tune Daphne sang when she cleaned up Shaggy and Scooby.
- What Could Have Been: According to Maxwell Atoms the movie was originally intended to be relased in 2019 as a third movie for Scooby's 50th Anniversary and Atoms also was under the impression there was an earlier version of the script he never saw. The studio mandate to wrap up the Sheriff plot and the lack of continuation on other points tend to lean the earlier version was more similar to the previous two movies.
Trivia / Happy Halloween, Scooby-Doo!