The first to travel widely between the stars were known as the Endless. Much is told of the Endless--of their technologies, of their societies, and especially of the uncountable splinters into which their nation eventually shattered itself. Their history is glorious but above all tragic; though they unlocked the secrets of time-space, the stars, and life itself they were unable to master their own internal conflicts. But we must remember this: though their explorations covered millions of stars across endless light-years of space, even they are barely a drop in the vast sea that is the universe. The Endless got almost godlike capabilities through a resource known as Dust.
A war arose between two factions of them: The Concretes who were were immortal genetically modified Endless, and the Virtuals who were immortal virtual Endless. The war was telling and their civilization collapsed.
What remains now of the Endless are strange, disjointed traces in the forms of seeds, of observatories, of experiments, of cities and worlds and perhaps – though not all of this is clear or verifiable – in the forms of other peoples.