The new premise for standard D&D adventures is less on world-building, and more about building fantastic, isolated locations and points of civilization so that much of the world remains undefined, unexplored, and ripe for adventure.
The proprietors of the inn, and the local farmers, have a secret, however; they actually serve dark gods far older than even those served by the now collapsed empire. Their gods demand blood sacrifice on a regular basis and many a lone traveller who has had the misfortune to stop at the inn as the new mooon approaches, has found himself the guest of honor at a cannibalistic ritual to the ancient gods.
The Mushroom Kingdom: For untold centuries civilizations have risen and fallen, each built upon the ruins of the last. In ages long past, when the foundations for these cities were laid, powerful magics forged portals in the deepest parts of their waste aqueducts. The wisest sages have never found the exits to these portals, and would be deeply disturbed were they to find out the truth.
These portals were all tied to one gate from whence all manner of filth flowed into the sea. Over the centuries, the algae blooms and life that they attracted formed a basic reef, and then an island, then a small continent, at the center of which is a slow oozing volcano of filth.
Wild and bizarre are the inhabitants of this great isle, from the noseless dwarves that work the soil, selling fertilizer back to the cities that produced it along with mushrooms of all shapes, colors, and textures, to the giant dung beetles that roam the surface crust.
Most newcomers to the island arrive by accident. If they survive the trip through the gate and out the volcano, they must then deal with sicknesses wrought by the filth. Barring disease, there are still other threats, like strange turtledoves and living mushrooms of only base intelligence, the minions of the great fire-breathing orc shaman, who controlls much of the mushroom kingdom.
Some resist Bowser, the great orc shaman, like the humanoid survivors that litter the island or the more intelligent diminutive race of living mushrooms, like the more adapted nose-less, hairless dwarves, who wear giant mushroom caps as hats and look much like toadstools in the right light. These inhabitants worship a porcelain god, and believe that one day the filth will all be flushed away.
Adventurers who happen upon the mushroom kingdom are often recruited to help fight the orc shaman and his minions, though will most likely spend much of their time searching for the portal that will return them back to their homelands.
It is rumored that the orc shaman, Bowser, keeps a human woman hostage, who is rumored to smell delightful, like the scent of peaches.
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So are these for Points of Light or some other setting? I'd like to see more info on the PoL setting myself. I know I was thinking of a hidden city or town of all Tieflings.