In the first soundtrack piece there was an audio track of crows in the piece. The crows were added in in reference to the Hitchcock movie “The Birds” (and the grossly underrated Birdemic). They create a primal sound of the area making it seem more menacing and dangerous. The lack of silence in the beginning of the piece combined with these bird calls beckoning out at random is very threatening. Screenshots below.
As you can see it is a very simple waveform, very little room for flexible design choices here. The first thing I did was add a massive reverb onto the crow caws to emulate the environment that the character is in. This made the low frequencies sound way too boomy, so I added on the EQ8 effect you see on the right to reduce the the lower frequencies and thin out the sound of the crows. This made them sound a whole load more scary. The sound effects of the crows can be listened in isolation here: https://soundcloud.com/svrdophobia/crow-caws