Bibbit's Lair

The deeper you travel, the more organic the tunnel walls appear. The yellow-green mushrooms have been replaced by pustules, glowing with terrible power. The walls themselves go from a fleshy pink to a dark red, and they almost seem to move, quivering with life. It’s not a good sort of life, though; it’s the sort of life that brings death. In fact, the deeper you travel, the more the branching and narrowing tunnels seem to represent blood vessels.