Welcome to the World of Arvenfall
Arvenfall is an ancient land. All the powers of the High Magic and of the Collected Council of Divinities reside upon its green and growing shores.
Humans are the main inheritors of all the civilized land, with other races being hidden away, for the most part.
Ruined civilizations, one after another building atop those before, scatter the countryside. Ruins and magical sites are just rare enough to evoke fear and legend in the general populace, and just common enough for for those bold enough to venture inside to be able to find adventure aplenty.
All the different magical, elemental, and extraordinary planes are directly connected to Arvenfall. But they are not as the usual, for the most part. Arvenfall is a flat world, and all the seas that fall off the edge of the world pool, endless depths downward, into a great sea. This sea has only one outlet, the river Styx. This river flows out into the lower planes.
High above Arvenfall are the celestial realms, resting on clouds and flying in great cities.
The elemental planes are intertwined with Arvenfall. Fire elementals spring from magma and forest fires. Water elementals inhabit seas, rivers, lakes, streams, and springs. Earth elementals spawn in the deep caves and chasms of the earth. Air elementals are in all the air, but usually keep themselves to high places and the upper reaches of the clouds.