There is flora and fauna in Hell. Flowers exist, but they're usually stunted and stink of meat, or else are carnivorous, luring their prey with a sweet scent that is poisonous to insects and, in enough amounts, some of the weaker Damned. The native Fauna of Hell is as bad or worse than the flora. Insects exist, from stinging gnat-like things to huge, ugly bugs like horseflies that love to prey on Damned. Much of Hell's other surviving fauna look like twisted crossbreedings between insects and mammals.
Some unclassified fauna are large and nightmarish.
They're very rare and usually live in outlying places where Fallen can't kill them. Most of Hell's soil is sandy and dry when it's not pure rock or swampy river mud. Metals are rare outside of mines, and all metals must be mined from deep within the mountains. Most metals appear to be earthlike as players would understand them. There is a recent discovery of ore that refines into a reddish-tinged liquid.