Sometimes, you can shock a player by placing something across their entire screen that they don't suspect. Such as, I've seen in Sunday the 19th, letters written in blood pop up on your screen. However, after this happens once, it is just annoying. So, maybe do something like that a couple times in your game, but limit it to happening once.

The only two games I've ever played that actually scared me were Doom 3 and The Suffering. Doom 3 was more successful because of its sound a lighting, something that you won't be able to pull off so well in a 2D game. The Suffering succeeded due its psychologically disturbing nature.

What do you think came before 3D games??? And do you think no one was ever scared of them??? That's just strange to suggest a 2D game can't scare someone. You just need to learn about what make's something scary, perhaps play a lot of scary games?

Things like building up to a climax, creepy music, fear of the unknown, false enemies (Hallucinations) and many more.

I don't mean to put you down but I believe in telling it to people like it is.


Scary 2D Games :

Darkseed << F*ing Scary
Nightmare on Elm Street << Quite scary for what it is.
Escape From Hell << Looks very creepy.

Scary 3D Games :

Condemned <
Dead Space << Alright<br/> Hexen II << Will F*ing freak you out.
Heretic << Has it's moments, great atmosphere.
Heretic 2 << Very scary game, amazing mechanics.
Quake << Scary as F*
Quake II << ^^ but not Quake III, that sucks.

Eternal Darkness was insane.

This is a difficult one.

2D has many positive traits, being able to invoke fear is not high on the list. What you do have though, is the ability to tell a story, just like any other game, regardless of the aesthetics, so I think that's the best approach. Your plot will need to be well written and leave the player feeling sick in the stomach after experiencing your creation.

Remember, even books can be horrifying. Spend a couple of months locked away in a room, only with greats like Hell House to keep you company, and inspiration might just come your way.

Come up with twisted scenario, throw in some nasty surprises, and make sure you have one hell of a graphics artist.

Good luck!

What you could do is spawn them in a dark environment with, possibly lights flickering down a 1x1 corridor. Along the walls could be glass and from there, at some point when a player is running down, you could make a body being thrown from the glass... That is some amount of artwork already, but, it would be a good touch :) And, you could make the player move slow instead of rushing down the hall. You could also add some fog! And you know... when you exit this long corridor, you could have "The cake is a lie."x3 in blood as OrangeWeapons suggested. You could also add... I guess based on the time period, chests? Drawers? to obtain items... have some fights in the beginning, soon after you leave the second room... The fear of Death is always something in a game when you've gotten so far and having to do many things over.

Invoking fear in a game is not that hard, but you have to know how to do it:

1. Lighting. Everyone is afraid of the dark,l not because it's dark but because of the unknown that waits behind it. If you're in a dark room, you're fine, now imagine being in a near pitch black alley way. Or even your own home, but imagine it empty of all furniture.

Most fear is "fear of the unknown" If you know there's a monster down a hallway it's much less scary then if you don't know what's down a hallway and suddenly see a pair of glowing eyes. Once the mystery is gone you lose a substantial amount of fear factor. Keeping things dark is one way of keeping things mysterious and frightful.


2. Survivability. If you can just outrun your enemies or beat them to death easily then it's not going to be scary. Doom three was fun but I always felt confident that no matter how horrifying the creature, I could kill it. Or with Silent Hill, some creature were harder to kill but simple to outrun. The less confidence that you have in surviving the more horrific it is.


3. The monster. People want a good monster, something to scare them. The problem with monsters in games like Doom is that they're simple to identify. An imp is humanoid and can only really mess with you by throwing fireballs or smacking you, not that scary. The cherubs however were small, they hid easily and they were like freakish baby bee things. They would leap out of the darkness and [expletives deleted] if you weren't careful. The spiders were this way too, but their movement speed was moderately slow and were much less scary to me. The monster in amnesia is humanoid as well, but horribly disfigured, which adds a question to your mind: "How did it survive being so disfigured?" The answer? It's unkillable. Nothing is scarier than knowing that you can run but you can never hide, or the other way around. Being able to do both, or neither, takes the suspense out of it. If the monster kills you too easily it's a buzkill and if the monster just falls over for you it's too simple.

Amnesia is a game that pulls of these three pretty darn well. The lighting is key to the game but if you're lit up then the monster can see you, making your only friend in the game, light, also one of your biggest flaws. Survivability is low, this game is trying to kill you, albeit a very lax form. The monster isn't frequent enough to cause constant fear, but it doesn't let you relax for too long either. The monster itself is an unkillable force that will chase you to the ends of the earth. Luckily it's slightly slower than you and has trouble with doors, until it bashes them down that is.


tl;dr

If you want a good horror game you have to follow 3 key rules. 1. Keep it dark enough to leave the player mysterious as to what lies in wait. 2. Don't make the player strong enough to survive easily, death should be at their heels at nearly all times. 3. The big bad has to be a true big bag, unkillable, unstoppable, and relentless in finding a way to stop you breathing.

That's my view on it though.

edit:
notable lighting: Doom 3, Half Life 2, Left4dead, Amnesia
notable Survival: S.T.A.L.K.E.R, Amnesia, Resident Evil
notable big bads: Nemesis (RE), Mr. Struts (Amnesia), Undying Necromorph (Dead Space1+2)

Ah indeed, though the survivability rate makes it seems less creepy. I really enjoyed the parts where you had to run away from her or die instantly, those were great!

Sound is a crucial part, as well.