From Screenrant:
"The Asphyx is smothered by the skin from its own flayed body, wraped and twisted over its face. The skin is pinned in place along a string of nerves and muscles, stripped from its flesh to reveal its heaving chest as it struggles to breathe against its own disfigured skin." I played with a few versions of this.
The Asphyx really hit home for me and I think it came through in my concept sketches.