Thank you for that feedback, this definitely would need context to fit into in a campaign and isn't very drag and droppable. In my mind, this would be best played in a game already featuring Eldritch beings like Cthorkborg with this being a machination of the cult that the party makes a Hail Mary to use to potentially stop the end of the world and buy time to deal with the new problem. Like personally, I would open with my Silent Night going up the mountain to have an eerie atmosphere and a stalking horror hunting those traveling here.
The Cold and Deathless Northern Darkness Jam » Entries » Conquest of Cthulhu: An Adventure for Mörk Borg