It's a very damp space that smells quite awful. They make squelching noises as they walk and ground feels very soft. They further they get in the more narrow and hard to walk the space gets.

But there's a light at the end of the tunnel. And a pit full of what looks like lava and in the lava there are snakes made of fire jumping up and down. There are some narrow platforms and planks made of stone that can be climbed to reach the other side, but the snakes can jump very high and will try to snag them.