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Xin-Gastash was the capital of the Thassilonian Realm of Gluttony, and was destroyed by the great event that brought down the rest of the kingdom: Earthfall. Constructed underground so that the necromancers of Gastash could practice their arts without the detrimental interference of the sun, Xin-Gastash was said to have contained Thassilon's greatest bathhouses, drug dens, and feast halls. Though much of the city was destroyed and sealed off from outside contact by the earthquakes that shook Golarion following Earthfall, an obstructed entrance to Xin-Gastash exists beneath the mountain the orcs of Belkzen call the Sleeper.1


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