I was for some reason playing a video game where everything was dark and the player was continually falling deeper into an infinite abyss. There actually was some terrain somewhere, but you'd soon pass below it somehow, maybe through big holes in the ground. Kind of like what happens if you take the Prawn suit off the edge of the map in Subnautica. It was a depressing game to play because it seemed very hopeless, but if you did things just right, things would work out, somehow. While it was very hard to see and most of the world was black, there was a little bit of lighter black here and there, because things reflected a little bit of UV light, and I guess the character had a visor of some sort that allowed them to see it. But even then you could only barely make out the outline of the terrain and it was easy to accidentally fall off the edge, which was maybe necessary at some point.

The theme of falling down further and further into more and more nearly hopeless places was also a theme in the part of Hel that I made while listening to Assemblage 23, to help set the depressing mood.