Halloween is the perfect time to gather friends around the table and tell spooky stories, and nothing is better for storytelling than Dungeons & Dragons. Fortunately, Wizards of the Coast has released a lot of material in the last year that is absolutely perfect for horror one-shots, and there are a plethora of ready-made adventures in a multitude of unnerving moods and settings available for DMs to integrate into their game.
Source:https://www.cbr.com/dnd-halloween-one-shot-ideas/