On South Drak Isle, a vast, arid desert bakes in the sun. The surface is as barren as it is deadly, with sand dunes stretching to the horizon. Although the obvious danger of a sun blasted desert is obvious, the true dangers lie beneath the sand.
The Sand Ocean is bound by jagged mountains to the north and west, the Defiled lands to the south, and the Farwest Depths to the east. Massive, scorched dunes of rough sand and talc-like silt cover the surface. Occasionally, ancient and erosion-smooth ruins will peak above the sands, only to be just as quickly consumed again.
Underneath the shifting surface of the Sand Ocean is a strange subterranean zone, not quite surface and not quite Underdark. Massive caverns, underground oasis', temple ruins, ancient catacombs, lush grottoes, and even exotic, bustling cities of snake-like humanoids teem just under surface. The entrances to these varied biomes are rare, well-hidden, and sometimes temporary, depending on surface conditions.
Legends tell of an Ancient Blue Dragon that slumbers under the sands atop a massive treasure hoard. Some legends describe how the local Yaun-Ti worship this dragon as a deity (with the hope of absorbing its power for their own uses). Other legends describe the dragon being a carry-over from the Old World; a being so powerful it survived the New Genesis.
Ash Mo'dan , the Zamberian Draco-Lich, is known to dwell in his vast necropolis under the Sand Ocean, sending his undead minions to attack the Defiled to the south, and do his bidding the world over.
The Yuan-Ti are suspected to have a massive civilization under and within the Sand Ocean, worshiping their strange gods and pursuing their ineffable goals in temple-cities full of ziggurats, pyramids, aquaducts, and lush pools of fresh water.