There is the Physical World, Omo.
The two Moons, Derwan the Blue and Krand the Red.
The Sun, Akon.
The Stars, whose constellations and mysteries are Nyme’s.
and The Blackness Between, Zir.
The Cosmology is Geocentric.
That is, Omo is at the center of the Universe, and everything revolves around it.
Omo is small in comparison to Earth. It’s diameter is roughly 2,000 miles, an equator that is roughly 6,200 miles, and a surface area of roughly 3 million square miles- making all of Omo’s continents and oceans together smaller than the total land area of Brazil.
There is a 1 degree latitude change every 17.2 miles, so a trip due north for one game month (40 days) travelling at 20 miles per day sees the climate change as if you had gone from just south of the Sahara desert in Niger (Latitude 13) to Helsinki, Finland.(Latitude 60)
This was intentionally done by the DM so as to be able to reasonably detail the world within a lifetime.