Fallout 4 is currently free on PC (and Xbox One) which means you can check out the extensive mod support for the game. So why not go ahead and download the fantastic looking Fallout 4 horror mod, "Pilgrim-Dread the Commonwealth"?
Check out the absolutely thrilling trailer for the mod below.
Pilgrim is an atmospheric Horror ENB that tweaks Fallout 4's weather system to create the ghastly overcast darkness seen in the trailer. According to the mod description Pilgrim also includes "lens emulation, film grain, adjustable letter-boxing, optional sharpening, and a lift shadows funciton that can be disabled for deeper shadows." The new camera mod even emulates digital cinema cameras, giving Fallout 4 a truly Hollywood horror movie look. You'll also be able to listen to an original soundtrack and music system that changes with the weather, but also the exploration and combat soundtrack, replacing the "vanilla music."
The mod also includes two presets with lowered quality settings for weaker systems, although the regular mod will drop your FPS by a smidge.
Pilgrim is inspired by the 2015 horror film The Witch by Robert Eggers, a film about the haunting of a Puritan family in old New England. There are even plans to replace the main character's sidekick Dogmeat with Black Philip, the terrifying goat from the film. If I were you, I wouldn't listen to whatever lies Black Philip tries to tell you.
Instructions to download and install Pilgrim can be found over at the Nexus Mods page. Pilgrim won't work with any pre-installed weather mods, and only works with the base game (no DLC levels). Since Fallout 4 is free until Sunday, it might be a good chance to give the mod support a little test run, and Pilgrim looks like an absolute blast.