Polysol - Crystal sphere with no large central sun, necessitating lots of Apollo style solar chariots (or Ra style solar barges) that each serves its own locality about the size of a US state. Potentially the time of day, length of the day, and the direction of the sun's travel may vary between regions in an unsynchronized way. (Edit: alternately they could be perfectly synchronized and with a simgle sun god controlling all of them, in parodic contrast to D&D's usual nonsensical situation of multiple non-collaborating sun gods but just one sun)