So I was thinking about horror games, and why they will often fail to inspire any real sense of fear despite the developers going out of their way to make the most horrible and grotesque monsters they can possibly think up.
So I thought of one game that scared the heck out of me, which was 7 Days a Skeptic. What really scared the heck out of me wasn't the Jason-esque villain, it was how seriously downhill the game when when the antagonist finally picked up some speed. To elaborate, during the final stretch of the game, you're by yourself as a metaphysical psychopathic killer stalks you. While the fact that he could kill you in one hit was scary, what was scarier was that you COULDN'T predict where he'd show up, he'd disappear and reappear seemingly at random (though, once you get to know the game, it's not random at all) and all you could do was stun him with a taser gun, which only provided temporary relief.
Then I thought of lovecraft, and why his stories are scary, and it's summed up simply as "The fear of the unknown", which is quite eloquent and powerful as a primal fear.
So I thought of a game idea combining the ideas of unpredictability and the fear of the unknown. Also, a good heapin' dose of helpless and vulnerability won't hurt.
Basically, through reasons both arbitrary and contrived, you'd be a guy/girl in a haunted mansion.
The object of the game would be to explore the mansion, and find means of continuing your existence within certain times limits.
Said mansion is haunted, but not by ghosts, it'd be more like the hotel from the Shining, where the mansion is actually a living thing. Just thought I'd start with that to give you an idea of where I'm going with this idea.
For starters, the entirety of the mansion is dark. When I say that, I mean that almost the entire mansion is near pitch black. Your character will have a flashlight to alleviate this problem though. To put it simply, your life revolves around this flashlight, and for good reason.
To explain the mechanics of the flashlight, it's a wide angle flashlight that provides a constant cone of illumination whereever it is pointed. Besides illuminating whatever it's pointed at, it serves as one of your only sources of defense against the many nasty things in the house. Because, as you explore the mansion, you would see things skulking and creeping in the darkness, thing which simply disappear (as though they never existed) or dissolve quickly in the light. Some of these things are hostile, and constantly dogging you, and your flashlight is your only defense against them. I'll elaborate on that further in just a little bit, but what's important to note is that the flashlight is NOT infinite, nor does it regenerate it's own power. What I mean by this is that there would be a counter in the corner of the screen or something, constantly ticking down your flashlight's power supply. If you run out, you're pretty much at the mercy of everything that might be lurking in the shadows. To get more power, you can find rare batteries to replace dead ones, or you can return to the Mansion's 'safe room' (which will be elaborated on later) which has a charger. I'm somewhat reconsidering the idea of a counter though, since it might ruin immersion. It might be better if the flashlight instead gets dimmer and dimmer, then start to flicker, and then go out, so that it doesn't disturb the atmosphere and provides another layer of suspense in the form of the guesswork you have to do as to how much power you have left. Also, throughout the mansion there'd be mirrors, and light would reflect off of them, preferably in a realistic fashion.
While the flashlight is your main source of light, it's not your only one. There would be matches around the mansion that you can pick up, and use with a button or something. These matches provide a few seconds of dim illumination in all directions. These are more haphazard, since they're finite and can't be easily replenished. However, there would be other uses in the game for the matches. For example, there would be candle's and candle holders all throughout the mansion, which you can light to give extra illumination, if only for as long as the wax candles can hold out. Also, there might be other things like fireplaces, kerosene lanterns, torches, and the like, but you have to be able to light a match in order to use these.
What I'm trying to get at is, you can't use the matches everywhere. There might be places where the air is too moist for the matches to light, or there might be places where the air is filled with flammable fumes and lighting a match will cause an explosing, killing you instantly. To be fair about it though, your character would be able to smell said gas, then loudly exclaim something to the effect of "It smells like gas in here" in order to let you know it's not safe. I also think it'd be a good idea if your character can throw matches/other sources of light for whatever reason.
An important part of the gameplay would include a day/night system where time passes, and the sun will set, the nasties have the darkness and can come out, and then after some time, the sun will rise, and the nasties will then cease to exist. The game would continue like this cycle until the game's end. What's important to consider though, is that since the mansion is a living thing, that it actively changes itself depending on whether it's day or night. What this means is that there are certain things which can only be done during the day and other which can only be done at night, and there might be puzzles which require a little of both. To help with this day/night system, your character would have an old-timey watch to keep track of time and the stage of the moon. Nasties could also fluctuate wildly depending on what time it is, and what stage the moon is at. For example, nasties would be very bad at midnight, but very VERY bad at midnight during a new moon. Also, for a special event, I think it would be cool if there were solar/lunar eclipses, which would send the nasties flying into uncontrollable frenzies, such that even sources of light have trouble dealing with them.
I mentioned a 'safe room' earlier, and I should elaborate on that. In the entire mansion, it's entirely dark, except for the safe room, which is lit by makeshift lamps/lights 24 hours a day. This room is your safe haven, and where you can store supplies (as your inventory is finite), restore your health, sleep for X number of hours (so you can switch between night and day quickly), recharge your flashlight at a special charger. However, the game will tell you when you have access to the Safe room that he flourescent lights are burning out, and that you only have X number of days to find a new one, necessitating that you explore the mansion as quickly as possible. The safe room + flashlight + Helpful note (which tells you how the room works) is prepared for you when you start the game, hinting that there's other people in the house that are desperately trying to survive.
The charger requires special consideration, as, ideally, it doesn't charge the flashlight instantaneously, and the flashlight can't be used as it's charging. This isn't a problem when you have the Safe Room and can simply place the flashlight to charge, and then sleeping for some hours until it's at max charge. However, this becomes troublesome when you have to wander away from the safe room, or when it becomes unavailable and you have to use less conveniently placed chargers.
As I somewhat dislike the concept of puzzles in a survival horror game, there wouldn't be anything like slider/block/jigsaw/math/word puzzles. Instead, you'd have a cell phone, and a creepy man with a raspy voice would be calling you throughout the game, giving you hints, clues, and generally trying to be guide you and be helpful. However, this man's allegiance would be quite hazy, but you need his help to continue. As well as the Raspy man, there would also be the Dark Stalker, another character that sneaks into your room when you're sleeping and leaves notes and presents. There would also be traces of this person around the mansion, in the form of footsteps, other notes, and if you're observant, you might be able to see him in remote locations. He absolutely refuses to introduce himself though, and seems to have ulterior motives of his own, perhaps those that are in direct conflict with those of the Raspy Man's.
Now, with the horror part of the game, while there are nasties, these are only a small subset of your worries. The nasties are actually quite conservative, and are barely harmful, if at all... At first, anyway. The mansion though, since it's a living thing, will directly attack you. These are not literal attacks though, instead, it's things meant to damage your perception and expectations. For example, when walking near a window, the window will spontaneously explode into shards, and it will appear as though a nasty has jumped into the room, when it was in fact just an illusion. A second example, doors would fly open and close, as though things are walking through. Thing might change places, unseen forces might knock you down stairs, things might suddenly drop from shelves, etc. Another example, during a special scene, it would seem that mansion has transformed into a pleasant place, with smiling party-goers that are all seemingly harmless, and then drop the hint that turning off your flashlight is a good idea; it's not a good idea, at all, and it has to do with nasties.
I've been mentioning "Nasties" without actually explaining what they are. Nasties are like ghosts, and these ghosts take many forms. The nasties can be seen as little dark figures and shadows moving in the darkness, but can never be seen if you try to find them with your flashlight. Alot of nasties are completely harmless, so worrying about each and every one is pointless, but more than a few are not only NOT harmless, but out to hurt you. Nasties are VERY afraid of light, and even the strong ones will be afraid of approaching you, for fear of getting hit by your flashlight. As a metric, the weak ones won't be interesting in anything more than playing tricks on you, making it seem as though there are people standing and walking around in the darkness, will take the form of dark children, and run past your knees when you open doors, and generally trying to confuse you. The ones that are actually out to hurt you though, won't only take the form of humans, they'll also approach and hit you/grab you/throw things at you/etc.
As a rule of thumb, ideally, Nasties get more and more aggressive the more days you spend in the mansion. So at the beginning, you might be able to go around the mansion with your flashlight off without too much harm done to you, but later on, you need to cling to a lightsource no matter what, or suffer a horrible death by things you can't see. If you take too long, then bold nasties that aren't afraid of your flashlight will start appearing and they won't be afraid to get hit by the light in order to get close. Some smart ones might appear as well, which will knock your flashlight out of your hand. Then eventually, if you spend a very long time in the mansion, you'll notice that the nasties get less and less human, and take more deranged shapes. There might even be a few that can take a second or two of being hit by the flashlight before dissolving.
Since the Nasties and the mansion exist in harmony, they'll work together, and make it seem as though the walls are moving, that creatures are coming out of the walls, or even shake the floorboards violently in order to trip you. What important is that they don't attack you so often that you get used to there attacks (and thus loses the 'fear factor'), but often enough that you have to be constantly paranoid from attack. They must remain mysterious and impossible to give names or identities to, in this way, they will always be an unknown factor. They must always the thing in the dark and you don't know how it's going to act next, or from where it's going to attack.
One thing to note, however, is that it's futile to 'hunt' the nasties, as they can never truly be killed, and more and more will continue to appear.
It should be noted though, that your character isn't trapped in the mansion, but is forbidden from leaving. Not by arbitrarily locking the front door, but it could be that the haunted mansion is surrounded by haunted forests, and if you try to leave the mansion and venture into the forest, then your character is assailed by countless hordes of the strongest nasties.
Also, I think it would be cool that if you explore deeply enough into the Mansion, then you could find other people with various skills. Like you might find a trapped cat burglar that can unlock doors, or a strong guy that can lift really heavy things.
God, I just thought of this when I woke up, and I wrote all this...