Much of the art we were inspired by were book covers or comics of various Dying Earth type stories (Vance is one of the originators) and that formed the basis of what we created for our Cosmic Fantasy setting.
A ruined universe at the end of time. The big bang had long since receded and the big Crunch was nearly complete when something arrested it. The natural universe ground to a halt. This ruined stasis has persisted for millennia more. No one remembers how it happened, but they know the great maelstrom spinning at the center of it all only come into existence after the stasis started. Within this stasis some solar systems and planets remain but are most are barren places with the only inhabitants the crumbling remains of innumerable civilizations.
However some beings survived it all. Whatever stopped the big crunch also broke the remaining reliable laws of physics and real space became quite hazardous to travel and threatened to maroon the survivors. The mysterious architects of the maelstrom created an alternative: the rifts system.
Scattered across worlds were rift gates. Gates that can be used to travel to a strange space highway that accesses other gates. Riftspace is a mysterious confusing island in a sea of nothing, but it allows travel between the gates. Only legends remain of what Riftspace is or how it was created, but whatever the truth a maelstrom spins at its center. A twin to the one at the heart of the universe. While the true maelstrom spins across a space larger than a dozen solar systems, the one in Riftspace can be measured in kilometers. The connection is unknown.
What is certain is that the maelstrom is alive. No one knows what it wants or even if it wants. But sometimes it "speaks" to mortals. Sometimes it grants power. Sometimes it takes minds. But through it all, factions have risen that try to control riftspace and with it the ability to travel between worlds.