What's scary
 

I want to make a horror game, but the only issue is I'm not sure of what to do for what the player will be against. I don't know if i should just make a crazy guy with a motive, or a poltergeist or if i should make a monster. If i were to make a monster i don't know where i would start first as what the monster should look like, what he should be about, and/or if he had any "powers".
What should i do? If i make a monster any advice on how to make him look and what he should be like?

I'm thinking the game will take place late 1800's if that makes any difference

Definitely make a monster, maybe a strong/beefed-up killer zombie?

I love the unseen... things that lurk in the shadows that you really can't quite get a bead on. I also enjoy when the sanity of the main character is called into question, especially when the antagonist orchestrates the mental breakdown.

If I choose and kind of moster I would tihnk in the abstract reflect of the protagonist, who don't accept her/ his past and in the end well an history which doesn't have end like a cycle where you become the monster

Dead Space was so scary for me that I couldn't play it.

I think the elements that haunted me most:

• Lighting - Key parts where lights would flicker on and off; Same goes for Bioshock
• Sound - I definitely had to turn the sound down sometimes
• Utterly insanely creepy monsters - Ok, this will vary from person to person but I lost it with the Dead Space Aliens. And, actually, the Bioshock Splicers were pretty damn creepy too.

Feeling of helplessness and being trapped are key. Like the game mechanics itself is one big haunted house.

Dead Space is a great example of how to make a horror series because it started out really good, very creepy and atmospheric with the perfect mix of action and horror. As the series went along it focused more on bigger weapons, bigger enemies, and you always seemed to have ammo and health on hand... it just evolved into an action game by the 3rd entry in the series. I'd like to see somebody start with 3 and then play 1, I think that would be interesting.

A truly scary game is Amnesia. Dead Space has nothing on Amnesia. I hear Outlast is very scary too, but I have not played it yet. I don't consider Dead Space scary.

I loved Manhunt and Manhunt 2.
Even though they turned into shooters towards the end.
The storylines, the settings, the music, the characters,...
You could hear psychos mumbling in the background, when they heard something they started yelling crazy talk,...
And the moments when they suddenly jumped at you out of nowhere and come after you were genuily scary.
In part 2 the main character gets sick and throws up after his first kill.
All this is making me want to play the game again.

I really liked to see something unique like the first Bioshock had