They tie a rock to your feet and throw you in a pool of sludge. What you hit as you descend is not the floor, but a layer of corpses you now have to go through. And this is before you reach Oblotten.
The production is surprisingly polished and researched. Give your eyes time to adjust and you'll see shapes in the darkness.
These guys pile layer upon layer of fear and horror upon you. Don't like it? They won't even bother showing you the door. It's too late, anyway. You're not going anywhere.