Difficulty punished by death in horror games is a must.
Without death in those, then there's no real threat of doing things in the game.
A comparison example would be Doom 3 vs Quake.
Sure, Doom 3 has a lot more "horror" in its visuals, with it being super dark, with scary zombies and what not, but you realize half way through that you can just blast through **** easily.
On the other hand, Quake wasn't particularly dark, the monsters weren't particularly scary, and the graphics are much less detailed, yet I found it to be much scarier, because an enemy could come out and destroy you at any point.
My point is that death is a necessary consequence in the horror genre, and in many other genres, if they want to keep a good level of tension.
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