Are soundscares like loud noises that pop up suddenly? I usually prefer scary ambient sounds myself. Honestly if I ever made a horror game it's likely that when something scary happens instead of a loud noise, the exact opposite would happen: All the background sound would suddenly cut out.

One half-baked idea I had ages ago I would like to see in a game is for the game to check if a microphone is connected and if it is use it's input to create some kind of noise cancellation effect. I don't know if that is possible but it would be kind of spooky if when some supernatural event started it would start inverting noise picked up by the microphone and ramping the effect up slowly so any noise in the player's environment would be inverted away. Of course if they already were using noise canceling headphones it would be counter productive.

Soundscares are essentially like jumpscares for the ears, and can be combined with visual cues to make jumpscares, though soundscares are a lot more diverse and not everyone will be affected the same by common sources of soundscares like the one I referenced before.

A gunshot is an example of a soundscare most don't affiliate with soundscares but it usually has that alarming effect, though sometimes not.

Yeah, inverse soundscares are a thing, and I've perused those as well as reverse soundscares (playing audio backwards).
#audiophile