Basically, this is a question thread, asking for ideas on how to create a scary map. I will post some of my own ideas, and then, anyone with talent in this area, feel free to post your own!
Obviously, there are many lighting tricks to be applies to fear, but never forget flickers, and bluer tones of light, to create a cold feeling. Redder lights can create hostility. Don’t forget your colour theory!
Again, sound is an important factor, which i can’t cover all of of course. But, remember that persistent ambient noises can make people feel uneasy, especially sounds associated with bad things in certain situation, such as dripping, footsteps, metallic clanks. Screams must be used sparingly, as they are often heavily overused, and can be so over the top as to REMOVE the feeling of fear.
Gore. This is a huge topic area, and it is something which might seem simple, but must be executed with finesse. Don’t cover your entire game in blood ala Dead Space, but leave areas of cleanliness, perhaps followed by a sudden shock of gore. bloody writing on the walls can be good (See Doom3) or it can actually just be a bit tired (See Dead Space)
Jumps. Making the player jump 10 feet in the air, is, honestly, not that hard. But simply filling a game with horrific things leaping out at them (See Dead Space and a LOT of Doom 3) gets tired. Make sure there is plenty of anticipation, and perhaps even build up a load of tension, then have nothing happen. That’s a great tactic to make people feel tense.
So, your ideas friends! Feel free to use media as evidence!