Emissary
Luthor was standing in the cockpit of the Silent Wanderer, looking at an active lava site. It was actually quite far from the main settlements, and was discovered by one of the groups exploring the Inns lands to better understand and map them. Once the AI running the Midnight portal figures out how to launch satellites and keep them running and working in this environment, taking in consideration safety from any avian beasts, they would have a live map of the region. But until then, they would have to manually map everything out.
This particular lava pit was contained within a mountain range, fed by several different underground lava channels as far as he could tell.