human
Compose a short description of a foreboding cavern with water, slime, scum, and a cave-in.
assistant
This forgotten arm of the tunnels ends at a cave-in that totally blocks passage of water or creature. Perhaps once a stream flowed through here, but now it is a dead-end, causing the water to stop, the scum to accumulate heavily, and the air to become nearly unbreathable due to the decomposing layer of slime on the water's surface. Strange patches of light and shadow play off the walls as the scum layer is disturbed by the passage of wading adventurers.