I just had a pretty crazy dream. It's pretty rare for me to have a dream and actually feel any kind of fear, but this one may not qualify as a nightmare.
In the dream, I'm playing a demo of a really interesting horror video game, and most of it was first person. And because it was a dream, I didn't have the presence of mind to question the fact that, for the majority of the time I spent playing it, I was moving as if I was the character, i.e., I would do the jumping or whatever, instead of pressing buttons, although there were occasions that I recall pressing buttons on a controller.
The demo had something to do with exploring an abandoned house that belonged to a serial killer who targeted children, and the house was haunted. As I explored the house, I had the walkthrough for the demo on my phone. However, there was a lot of occasions when I felt something would attack me/my character if I didn't solve one of the puzzles quickly enough, or did something incorrectly.
I think one of the craziest parts was not even inside the house, where it was frequently really dark and had ambient music and such. I was outside, there was a heavily overcast sky, and this "train" was speeding toward me. It wasn't on any tracks, and it was as if it were formed from a part of the ground. The front of it was a face, the mouth was open. As it approached, it let out this loud and really crazy sounding moan, and the ground moved like the wake of a speeding boat, creating these huge waves.
When I completed the demo, there was even a part where the creator of the game (which was apparently an indie game) was asking for feedback, and that was when I woke, still feeling some of the fear I felt in the game, and covered with sweat. Although, I was also under both of my thick blankets.
Aside from the train, which looked cool but wasn't scary, I could definitely see that being a horror game, and I'd definitely like to play it. It had the feel of one of the scarier games in the Silent Hill series.
The voice in my head must think I'm deaf, because he keeps using sign language...