Trivia: The original title for the film was "Goosebumps: HorrorLand," which was based on the original script, which would have been a different story set in a haunted theme-park populated by "Goosebumps" monsters. The script was eventually re-written to be a smaller, lower-budgeted story. The film was then retitled "Goosebumps: Slappy's Revenge." Finally, it was retitled again to its current title "Goosebumps 2: Haunted Halloween." (Although oddly enough, home video releases for the movie have dropped "Haunted Halloween" from the title and simply market the film under a much simpler fourth title - "Goosebumps 2").
Trivia: Originally, this sequel was going to include all three main characters from the first film. However, due to scheduling conflicts with actors Jack Black, Dylan Minette and Odeya Rush, none were available and the script was re-written to focus on new characters. Black was later able to eventually free up enough time to appear in an extended cameo role, with several short scenes in the film's second half.
Trivia: When RL Stein gets out of his his car he sees a red balloon floating near a sewer vent and he says something along the line of, "I knew it! I did it first!" This is a reference to Stephen king's IT. Also Jeremy Ray Taylor, who plays Sonny in this film, played Ben Hanscom in the 2017 remake of IT.