If you're looking for a bit of spookiness as the nights draw in and Halloween approaches, developer The Chinese Room's Amnesia: A Machine for Pigs is currently free on the Epic Store; and if you're not looking for a bit of spookiness, well, there's some good news on that front too: Kingdom New Lands is also currently free on the Epic Store.
Amnesia: A Machine for Pigs is, of course, the follow-up to Frictional Games' seminal horror effort, Amnesia: The Dark Descent. However, while it retains its predecessors focus on gloomy chills, its story of a Oswald Mandus - a wealthy industrialist in the last days of the 19th century - and his vast underground factory, swaps clever systems for a more guided narrative experience.
Its scares aren't anywhere near as effectively orchestrated as those in The Dark Descent, but it's still a deliciously atmospheric tale of societal horror, with some truly unforgettable imagery.