Mine is Silent Hill 3. Its subject matter revolves around the fears of a teenage girl, like death of a parent, puberty, unwanted pregnancy (with a demon fetus, no less), mirrors (THAT ROOM shivers), and stalkers. The atmosphere is so oppressive and I cant play the game without having something else playing in the background, its that horrifying. I managed to finish Silent Hill 2 last year, which was like conquering my own fears. One day, I’ll finish SH3. One day.
It may be lame but alien isolation i have been booting up the same save for years and can never bring myself to play it long enough to finish.