When Stine arrives in town, he sees a floating red balloon near a storm drain and says, "I KNEW I had that idea first!" This is an iconic symbol for the Stephen King novel IT. Jeremy Ray Taylor, who plays Sonny in this Goosebumps movie, also stars as Ben Hanscom in It (2017).
Jack Black, while reprising his role of R.L. Stine, doesn't have much screen time in this sequel, not even appearing until minute 56 out of 90, 62% of the way through the film. This was due to his working on another film, The House with a Clock in Its Walls (2018), which was released 3 weeks before this one. Both movies are based on popular children's horror fiction.
Jack Black, who lent his voice to the evil Slappy puppet in Goosebumps (2015), this time gave way to Mick Wingert. The latter also replaced Black in another of his vocal roles, that of Po in Kung Fu Panda. Wingert plays Po in the video game and TV additions to the Po franchise.
Original drafts of the script set the film to take place in "Horrorland" with the numerous characters making an appearance in the books, "infamous" theme park.
Rob Letterman was originally set to return as director for this sequel, but was unavailable since he chose to work on Pokémon: Detective Pikachu (2019) instead.