Minecraft is already a horror-game, it's just building up tension to scare you more.
it's 2 am and you've been playing for 3 hours now, it's mostly calm, but as the never ending calmness continues you feel like you're being watched, as if the game generally is watching you, we get this feeling by our natural instinct, one of our instinct is, that if there is too much calmness or silence, a predator is present. Many animals have a similar instinct to that, it's also why birds don't like silence or they get nervous.
Now where was I…
… you feel unprotected and cold while playing this endless game in that endless world with nothing in it.
And then… cavenoise
You immediately get pumped with adrenaline and fear as if something were to happen, and close the program right away….
Those are the eerie moments of minecraft.