This was originally going to be a direct sequel to Mark of the Devil (1970), set in the same time period. Budget constraints resulted in the story being changed to (then) present day - 1995.
Selling on VHS above expectations, Moore Video quickly asked director Jason Paul Collum to film a Mark of the Devil, Part VII, but unhappy with how the film had turned out (he had no control of the final edit), he declined. They also offered him stories on the tragic cases of Jeffrey Dahmer (who murdered and ate his victims), Polly Klaas (who was abducted from her slumber party and killed) and Susan Smith (who drowned her own children in a lake). He also declined, feeling the stories were too recent and raw for the public. Ironically, Collum decided to film Mark of the Devil 777: The Moralist, Part 2 (2022) after he found the 25th Anniversary DVD release of Part 666 to be successful. Much of this film's cast returned for that sequel/spoof.
Many of the special FX/gore props were Halloween seasonal items purchased at Kmart and a local Halloween shop.
When hired to write and direct this movie, Jason Paul Collum had to research on his own (pre-internet) how many sequels already existed. He determined the most recent release was Mark of the Devil, Part V: Night of the Blind Terror on VHS in 1992. (It is the re-titled film Tombs of the Blind Dead (1972). He did so by reading a very limited publication called "The B's Nest."
Some casting choices were done because the actors had appeared in other films, which the producers hoped would add to VHS sales. Among those actors were Mick Wynhoff (America's Deadliest Home Video (1991) and Poltergeist III (1988)) and Lee Worrell (Aswang (1994)).