Domain of the Venom Cult

From the introduction: Level 6 of Dragon’s Delve has two distinct parts, the western, and the eastern. The two are connected by a long tunnel. The western portion is mostly abandoned. Long ago, it was utilized by followers of Master Mui Yan, a legendary expert in martial arts of all kinds. It has since been ravaged by fire, although portions of it are intact. Undead remnants of those killed in the fire still haunt the region, however.