It was a bit overwhelming to be thrown in with no instructions to a high intensity game like this. First thing I did was run off the edge and die. Which is my second big criticism, the fog is a bit too tight on the player and it feels claustrophobic. It's still exploring even if you can see more than 5 feet in front of you. Maybe keeping the fog unrevealed permanently once you've been somewhere could have also alleviated the tight feeling.
This definitely adheres to the theme though and it has a lot of really nice touches from the grave to the music and the death screen. It tells a story without having to tell a story which is cool. I also liked the meta commentary on "press escape to escape hell" and you're just leaving the game.