Ok, so I've seen a lot of concepts/games that are similar to this, but none that tie everything together.
The basic idea is a horror game that punishes you for being scared. The more scared you are, the more scary things happen, and the more scared you get, etc.
This is an online multiplayer game that needs a few peripherals. The game is played through VR, every user needs to have a mic, and everyone needs to be hooked up to a heart rate monitor (This could be plugged into a USB port or something, I'm imagining it to be like the Nintendo Vitality Sensor.
The basis of this game is very similar to Left 4 Dead or Evolve, with bits of Amnesia mixed in. There are 4 "Survivors" who are trying to defeat 1 "Monster". The monster's goal is to kill all 4 survivors. The monster cannot see very well, so everything appears blurry to him. However, it has incredible hearing. If the survivors say anything, or their heart rate increases, the Monster is able to hear this in order to pinpoint the location of the Survivors. So the survivors have to stay as quiet as possible to win. The monster cannot be hurt or killed.
The maps will all be user-generated. Each map will be required to have an objective that the survivors need to do in order to win (steal an artifact and return it to their base, restore electricity to a mansion in order to call for help, escape a forrest, etc.). Each map that is used is a random map taken from the monster's maps (e.g. if I'm the monster, the map that is used for that game is taken from the maps I have created, so I know the territory). The map can be covered in all sorts of jump scares are scary elements in order to try and get the survivors to cry out or have their heart rates increase. The maps can also have weaker AI monsters to act as jump scares/scouts, these CAN be killed.
Survivors can be one of several classes, here's just a few but I'm probably going to come up with quite a lot to add variety.
Soldier: Can deal out damage, but guns make a lot of noise
Engineer: Can interact with electrical equipment
Medic: Heals wounded/dead allies
Monster Hunter: Can Sense/Track/Find monsters with ease
Thief/Ninja: Can hide his heartbeat/voice from the monster for periods of time
Inventor: Can build useful gadgets using parts from around the map
Journalist: Can use the keyboard to send text-messages to teammates (there will be no team chat in the game).
Demolitions Expert: Can break into locked doors
Exorcist: Can repel monsters for a short period of time
Detective: Can use clues to figure out information about the map layout
Hopefully, the map building can be completely open source and players could even make their own monsters/scary things/other elements and add them into the game, keeping the game fresh and unique.
The 2 main problems I see are:
The tech isn't quite there yet. I think have a mic, vital reader, AND a VR headset is a bit much, plus, it's going to be hard to play a PC game when one of your fingers has a big sensor on it.
Staleness, this game requires fear to be interesting, and if a player plays the game and sees all there is to see, then the game becomes less scary and the entire idea goes out the window, this is why the player-based map building is so important, as well as having regular updates of scares/scary elements from both the designers and players alike in order to keep things fresh.