The theme for the October Blog Carnival is horrible. As in
What is it that makes a gaming session horrible? It could be wonderfully horrible, such as that time you were playing Call of Cthulhu and the hair stood up on the back of your neck as your cat screeched at an ‘empty’ closet!
Or it could be horrible as in that time you ran the convention game and the only people who showed up were a set of quadruplets who were all rules lawyers in the system you created.
Tell us your horror stories! Make them scary, make them poignant, offer tips on how to increase the horror factor or decrease the chances of your game turning out horribly!
One of my horribly best Call of Cthulhu games ever was at a con and all the conditions were wrong. We played in a room with several other groups who all played much more lighthearted games, there was no creepy lighting, no chance for music ect. But the dynamics between the players and between the players and the GM were great from the start and we quickly became immersed in the game to a degree that none of us really registered the noise and laughter from the other groups anymore. It was storytelling at its best.
Personally, a GM can get me with things in mirrors. TV screens works as well (Ringu, anyone?) And anything resembling Slender Man. A friend of mine freaks out when you describe glowing eyes looking in through the window. You can't use such things too often, but it can work out great when you do. It's more than awesome when you hit on something like that by accident (unless it makes the player freak out completely, of course) and watch the goosebumps build up.
Knowing that my GM won't hesitate to kill my character is also pretty horrifying, but I appreciate the feeling. I like to have my hands shake with adrenaline when I get into and hopefully out of dangerous situations with my character.
And then there's personal horror. It's not about monsters, but about the things the characters fears will happen to him and those he loves. I have a GM who is very, very good at that and I love him for it. This is not for everyone, I guess, because it confronts you with very real fears - what if my wife died, what if my best friend had a serious accident, what if some drug got its claws into my son? It can be overwhelming, especially if you have invested a lot in the character. But it's actually the kind of horror I like best in a game. Whatever that says about me.