A Legendarium, a Cosmology

Few mythologies beyond the Abrahamic religions (as far as I really know) have stories about the creation of the world ex nihil, from nothing. This is fine and good, as it allows me to begin the hidden history of my world thusly:

Once there was nothing, then the gods made a pocket of something, and called it the Universe, the one-song.

This was the First Age, the Age of Beginnings, and the first life of the Sun.

First, the gods bled, and from the burning hot fluids they birthed the sun, great furnace of creation, linchpin of reality. Without it, there could be no being, so the gods guarded it jealously.
Secondly, the firmament was forged to keep out unbeing from the Universe, and the burning stars of angels were set in it to guard what is, from what is not. Thus the precious Sun was safeguarded from the cold and hungry nothing of the void beyond.
Then, there was wild experimentation with what was possible, discovery of the limits of being, the first little splinters forming in the fabric of reality, and their careful study and exploitation. Great chunks of rock were pieced together, and set in the firmament, worlds and planes on which to create anything the Gods desired.
Finally, the Gods became aware of the undeniable power of the void beyond what they had made; Entropy. They saw it in the dying heat and light of the sun they had given of themselves to birth.
They tried eveything. They created beings on the worlds they had made to offer blood and souls to the sun to keep it burning.
It worked, for a time; but the wheels of entropy turn forever, and only crash round faster and faster.
Eventually, nothing the Gods could do was enough, and they knew it.
They held much conclave, and talked long and deep of what they would do.
They reached consensus. They gathered all blood and soul and worship as they could from their worlds, grew fat and strong on it, and cut their throats upon the furnace of the sun as it it died, and glutted their life upon the embers of the Sun.

Thus died the first Sun, and so was born the Second.
This was the Second Age, the Age of Birds, and the second life of the Sun.
The Gods awoke again, but to the confusion of the Reborn Sun, they were not who they were before.
The new Gods, for their part, knew a few things; for life and light to continue, they would need to grow fat and strong on the blood and worship of the living things that again now crawled forth from the rocks that hung improbably in space. They knew the angels that burned a great light on the firmament protected them during their duty. And finally, they knew that when the Sun guttered and died, they would need to feed the solar-embers their life-blood to relight it, and allow existence to continue to be.
All was well, and all was well, and the many folks of the birds opened the skies, as was provisioned for.
One day however, a wicked being calling itself Jaguar, who dwelt behind the mirrors, seduced one of the folk of the city of Xanadu, and a great breach was opened, which was forbidden. To seal it, the sun gave of its flame to weld the mirrors shut again, imprisoning Jaguar.
Thus, before its proper time, the Sun died, and the Gods killed themselves upon it to light the flame again.

Thus died the second Sun, and so was born the Third.
This was the Third Age, the Age of the River, and the third life of the Sun.
Again, the song began as before in the Second Age.
All was well, and all was well, and it was an age of spiritual enlightment and transcendence, lead at the city of Shambalha of the River-Font.
This time, the song ran its full course, and at the Ordained time, the Sun withered and died, and so the Gods again gave of themselves to relight the flame again.

Thus died the third Sun, and so was born the Fourth.
This was the Fourth Age, the Age of the Many, and the fourth life of the Sun.
All was well, and all was well, and it was an age in which were born a great multitude of creatures and peoples, the remnants of which still wander the earth to this day. This was the first Age in which Saints were born of the flecked remnants of gods of older ages.
One day however, the second through fifth of the Saints; The Minotaur, The Monkey King, The Ibis Sage, and the Lion Grandmaster, fought at the city of Daikuzu, and the crash of their battle wounded the world, and even the sun itself. It was after this day that the worlds began to drift apart, such that now to transverse the worlds is difficult and hazardous.
In their pride, the Four Divine Beasts were destroyed by the gods, though their names and titles survived them.
Thus, before its proper time, the Sun died, and the Gods killed themselves upon it to light the flame again.

Thus died the fourth Sun, and so was born the Fifth.
This was the Fifth Age, the Age of Horses, and the fifth life of the Sun.
All was well, and all was well, and it was an age of great exploration and rediscovery, for the ravages of the war of the first saints in the previous age had caused the world to crumple and reknit itself, as it would at the end of each further age. This was the first age in which mankind would arise ascendent, and conquer all the world. Their lords were the Great Khans, and they ruled from mighty Karakorum.
With the world united under one banner, the gods prospered, but when the empire fractured, and the world fell into chaos, the Gods panicked. In the cataclysms that followed, much was lost, and the Sun nearly died and withered beyond repair.
Thus, past the appointed hour, the Sun died, and the Gods killed themselves upon it to light the flame again, though it sputtered and sparked with fear for its light.

Thus died the fifth Sun, and so was born the Sixth.
This was the Sixth Age, the Age of Sands, and the sixth life of the Sun.
All was not well, for this sun was born hot and red, a result of the Chaotic end of the previous age. It was a harsh age, where rather than light and life, death was worshipped, and the mighty Monuments of Keshmet housed dead far outnumbering the living.
Thus it was, as the world was close to withering away entirely, the Sun called forth the newest generation of gods, and called upon them to slay it and begin again, before the damage was irreversible.
Thus, before the appointed hour, the Sun was slain, and the Gods killed themselves upon it to light the flame again.

Thus died the sixth sun, and so was born the Seventh.
This was the Seventh Age, the Age of Saints, and the seventh life of the Sun.
All was well, and all was well, and again mankind united all the world in one empire, whose great capital was Byzantium of the Pantheon, for many Saints were born in this age. This was an age of the great march of progress married with purpose, and the Gods rejoiced.
A wicked seed was planted however, whose bitter fruit would be tasted only when it was too late.
Thus, at the appointed hour, the Sun died, and the Gods killed themselves upon it to light the flame again.
But.
It was at this late hour that the Traitor-Saint, who by the will of the Sun would have their teeth crushed and their name blotted from all the world, betrayed their fellows in a misguided attempt at justice, and slaughtered them in the now desecrated pantheon. Glutted on stolen divinity, the Traitor-Saint approached the dying and bleeding gods, whose pooling blood dripped onto the coals of the sun. With his wicked blade, he tore at the still and bleeding forms of the gods, and wounded them utterly, to a final death. As the dying sun screamed in rage and fear, the Traitor-Saint realised what he had wrought, and fled from all knowledge.

Thus died the seventh sun, and so was born the Eighth.
This was the Eighth Age, the Age of Godless Chaos, and the Eighth life of the Sun.
All is not well. The Gods are dead, they were not renewed with the rebirth of the sun. Their bodies lie broken and scattered.
The angels, unfed with blood, are waning at their posts, and among their number are seen traitors, who have taken the title of Devils and stolen a world called Hell for their own, devious devices. Further, the ever empty void has crept into the eyes of some angels, and driven them mad. The first Demons.
Without the guidance of gods, man has again united the world under a single empire (nearly), ruled by his Dread Majesty from the Holy City of Babylon. They are without protection from those wicked things which, without the powers of Gods to hold them in check, become only more and more bold and numerous as the reluctance of man to accept them rises to meet it. Thus, man has turned to lesser powers to guide them.
The Church of the Heavenly Host, inspired in the hearts of man by the desperate Angels, offers them worship and blood, as the Angels believe themselves the most worthy and needful of it, sentinels of the Firmament as they are. They are deluded and wrong. Without Gods; they will one day fail and let the void flooding into the universe; or the Sun will die one final time, and they will fail regardless.
The Church of the Saints, which is man's creation alone, rallies the spiritual defence of man behind the Saints born of the floating shreds of Divinity left behind by ancient and dead gods. None in the Empire of All Humanity recognise the existence of gods. They just, know somehow, that the gods are either dead, long since left, or maybe never even existed at all.
There remains one psuedo-god. At the dawn of the Age, the new pantheon was born, but the old gods were dead and cold, and so they could not come into their glory. One among them had the strength and will to live, and so it devoured all it could. It ate its brother and sister gods, but that was not enough. It ate itself, but that was not enough. It ate everything, until not even its name remained, and finally it was satisfied; and now it is the Red God, the Cannibal-God-who-is-no-God.
The sun knows little of its past lives, but it knows this, there are no gods to save it this time, and the appointed hour of its death is coming. It knows it is that it is hungry, and it is panicking. For these reasons, it reached out to many worlds, a Bright and Burning Deity, to demand blood, and souls. Thus it fuels itself, and delays the end.
But the march of Entropy is irresistible. In the end, the Sun cannot escape its fate. Blood satisfies, but not forever. Souls satisfy more, but they are consumed utterly, and so the cycle becomes vicious, the more souls it consumes, the less blood will be produced. It was enough to start, but now it isn't. In the end, nothing will be.
The world fears for the plight of the sun, and so it reaches out to man, and those it touches who accept its words become the druids. The oldest and most feral, who understand the most of the Earth's designs, seek the corpses of the Gods, and seek offerings (willingly given or not) to revive them, and hope that their desperate strength will be enough when the Appointed Hour comes.

And so it is, in this Choatic and Godless Age; where the dregs of ancient, better ages succumb to desperation and apathy; where the order of the world decays under its own bloated weight; where the earth betrays itself out of desperate hope that another, better age might be born of the ashes of this one; so it is that the PC's become adventurers.