Considering horror is my preferred gaming genre, I roll my eyes at most creepypasta and SCP entries nowadays, (used to like Slender Man, but he's so overplayed by this point that even I'm sick of him) but one in particular still gets to me: SCP 087 (the haunted stairwell.) Something about being stuck in that dark, dank place with nothing for company but a child's cries and a possibly malevolent floating face just GETS to me. I've always hated stairwells (though my lifelong mobility issues have more to do with this than any real fear,) and that eyeless, nostril-less face makes me shudder every time. Those reports linked in the original SCP article are some of my favorite (relatively speaking) horror stories.