The Lhespenbog is a region of soft, spongy grassland sprinkled intermittently with rivulets and ponds. The grasses of the plains grow incredibly tall here and mix with cattails, mangrove trees, and creeping vines and moss. Giant eels, darting water spiders, a few chuul, shocker lizards, and various oozes and shines dwell in the Lhespenbog, feeding on one another and on foolish explorers who wander too deeply into its depths.
This marshy ground is also home to a number of undead. Sages believe that these creatures might once have been soldiers - part of a rebellion force that was cornered and slaughtered by troops loyal to the Shoon Imperium during the Seven Burnings campaign in the fifth century DR. Whatever the truth might be, the bog stirs with strange lights and sounds at night, and those who listen closely can hear the echoes of old battles being fought.