This is my vision of the Sekhet-Aaru, or the Field of Reeds from ancient Egyptian mythology. This was the abode of their afterlife god Ausar (Osiris), his bae Aset (Isis), and the spirits of the dead who enjoyed an afterlife mirroring that of the mortal realm. You could think of it as the Egyptian equivalent to the Christian Heaven.
I based the environment’s look off the as-Sudd, a vast papyrus wetland in South Sudan where people sometimes build houses atop these floating masses of vegetation. That gave me the idea of the Egyptian-style palace floating atop an “island” of reeds as shown here. As for the mountain in the background, it is based off Jebel Barkal in Sudan which was sacred to both Egyptians and Kushites.