The Radiant Isles exists as an inner world with verticality where continents float on top of each other, sometimes moving, sometimes static around a huge tower called the beacon. The Endless Sands, a massive ocean of shifting liquid like sand, loops around, encapsulating these continents and eventually meeting the freezing cold roof above the mountains where the sands funnel down the the Beacon, a colossal tower dotted with large gaps that connects the roof and floor. The Beacon itself acts as a source of light, dimming at certain points during the day. The sand within the Beacon is theorized to reflect off the strange magically imbued material of the Beacon, generating heat and light, especially around it's base. As a result, the mountains at the top are very cold with constant rain and snow while the Endless Sands are intensely hot at all times of year.
Irenians exist in the top continents, Galareans inhabit the lower continents the Endless Sands are where the Narakyians make their home. The floating continents have constant political change internally with the Galarean City States like Blackwells losing and retaking land constantly. Historically the Irenian villages have been subjugated by these city states on and off, depending the strength of militaries and the political shifting within the continents with much internal strife. However recently the political landscape completely shifted with the Illesh Kingdom, the Narakyians, completely and ruthlessly taking nearly all of the land within the continents.
(Kaede comes from Soona and Kor comes from Illesh)
I made this map so I could illustrate some sense into this world. It'll probably change down the line as I add more to it but for now it's a good reference. Soon I'll have a map of the desert!