The Drakans grew, in power if not wisdom, and discovered other worlds. In this search they found a power source, very different from Aether, and became addicted to it. This addiction actually led to an intolerance to Aether, and it remains deadly to them to this day.
Drunk with the power of their new source, they changed and became destructive, hunting the Humans they were set to protect. Five Drakans Ascended to a higher form and, calling themselves the Balaur, set out to systematically destroy the Humans.
To stop the Balaur, Aion raised 12 Humans, granting them enormous powers in addition to immortality. These were the twelve Empyrean Lords. Beyond this, some Humans, who were born with a sensitivity to Aether, spontaneously Ascended, becoming Daeva. The Daeva were less powerful than the Empyrean Lords, but there were many more of them and, like the Lords, they were immortal.
Thus began the Millennium War. For a thousand years, the war raged between the Daevas, led by the Empyrean Lords, and the Drakan, under the rule of the Balaur. Protected by the Aetheric Shield, the Drakan forces could make no inroads against the Tower itself, but wherever the field grew thin the Drakan would attack, taking a terrible toll on the lands and people of Atreia.
In time, the twelve became divided by their opinions of the war. Five came to be known as the Seraphim and, led by Lady Ariel, felt that the only way to stop the destruction was to seek a peace with the Balaur. Five, now calling themselves the Shedim, led by Lord Azphel, were opposed to any talk of peace. But the final decision was in the hands of the two Guardians of The Tower of Eternity, Lord Israphel and Lady Siel. Israphel was, however, already leaning to the Seraphim viewpoint.
But, in order for the peace talks to take place, the Aetheric Shield would have to be lowered so the Balaur representatives could enter the Tower.
To this day, no one knows who did it, but in moments the leader of the Balaur delegation lay dead and the Drakan attacked the Tower. While Lady Siel and Lord Israphel sought to hold the Tower together, Ariel led five Lords to the south, with all their forces, to defend the tower, while Azphel and the remaining five went north. The damage to the Tower was more that Siel and Israphel could repair, and the Tower was shattered, splitting Atreia in two as the remains of the world began bleeding Aether and atmosphere, racing towards the total destruction of the planet.
In a herculean effort which cost them every scrap of the Aether of their bodies, Siel and Israphel managed to reassert the Aetheric Field and prevent the total break-up of Atreia. Their effort also locked the Balaur inside of a nether region called the Abyss. In this effort they gave their lives.
When the dust settled, Atreia was now two halves. Due to the axial tilt of their world, the southern half of the world, Elysea, was bathed in the light of the nearby star, but her northern sister, Asmodae, was not so fortunate and, shadowed by their own land, Asmodae was plunged into frozen darkness. In the middle of the two halves floated the debris of the Tower and the equators, and this blocked their view of the other hemisphere.
Each blamed the other for the Epic Cataclysm, and each half believed the other half had been destroyed. The Asmodians blamed the Elyos and their Seraphim Lords for insisting on the disastrous peace talks, and the Elyos blamed the Asmodians and the Shedim Lords, believing it was they that had assassinated the Drakan ambassador. And so they grew apart over the next 800 years, never realizing the others had survived, and they nursed their blame and their hatred...
In this 800 year interim, each adapted to their new circumstances. The Asmodians, of necessity, grew hard and grim. Their feet and hands became talons and their visage darkened. By contrast, bathed in the sunlight, the Elyos grew almost ethereally beautiful.
Strange Rifts began appearing at random times and places. The Elyos sent their greatest Legion, the Storm Legion, into the rift to investigate, and what they found astounded them. The rift led them to Asmodae! But there were other discoveries to be had this day. An Asmodian patrol found the Elyos and, disgusted by what they saw, the Elyos attacked and killed the patrol. But the conflict had, by then, drawn the gaze of Lord Zikel and all of the Elyos were captured. ZIkel gave Deltras, the commander of the Storm Legion, the chance to renounce the Seraphim Lords and admit that they were sent to Asmodae as spies. When Deltras refused he slew them all.
Thus began the current war of fratricide between the Elyos and the Asmodians. But the worst news was soon to come... scholars of both sides discovered that a resonance existed between the two stumps of the Tower, and was drawing Aether each towards the other, draining the Aether into the Abyss. If this draining continued, both halves would become lifeless. And so each resumed the fighting, but with a new purpose, for each concluded that the only way to survive was to destroy the other and their stump of the Tower, thus severing the Aetheric connection.