"Aelar returned to the mortal realm in the body of a man, mortal flesh housing a divine being. He told us it was because of how the barrier worked, that if he ever exercised his full power he risked damaging it and endangering the world. But even as a mortal man he was different. He aged so slowly that a hundred years looked like no more than ten on him.
His command of magic, as you can imagine, was second to none. It was obvious why he'd come back. He loved us, so very much. He spent his days teaching us, showing us how to be better. His closest followers became the Pillars, men whose knowledge of magic towered over the rest. They were kings and high priests, and under their leadership and Aelar's benevolent gaze there rose shining cities. In those days men could cure any disease, solve any problem. There was no hunger, no war. Feats of magic and engineering meant few had to labor their lives away. It was an era devoted to knowledge and learning.
But though Aelar could teach us how to do many wonderful things, he could not change what we were. His love for us blinded him to the seeds of corruption that grew under his very gaze. Some say a demon which had hidden itself away tempted the Pillars into their fall. Some say it was just the weakness of men's hearts that led them astray. Whatever the reason, all that Aelar had taught them was not enough. Some of them came together in secret, determined to gain even more power.
It's said that they became convinced Aelar was hiding things from them, secrets that would make them the equal of the Gods. In their folly their reach exceeded their grasp, and with all they had learned they opened a hole in the barrier. The first Incursion erupted into the world with terrifying speed. The demons had been waiting, and we were unprepared. Our shining cities fell, burned to ashes as our best and brightest sacrificed themselves to stem the tide. The scale of the slaughter was... unimaginable. If not for the powerful magic Aelar had taught us, the entire world would have been engulfed.
But we held them. For just long enough we stemmed the tide. Those survivors we could gather fled across the ocean, to a continent they knew to exist but had never visited, populated by a people who had not received the benefit of Aelar's teaching. They became my order, the Exiled.
To keep them safe Aelar and the uncorrupted Pillars remained behind. They sealed themselves off from the rest of the world with a great work of magic, a bulwark that would keep the demons contained. And then, in one final battle, Aelar sacrificed himself to close the hole in the barrier. The Pillars died to a man to give him enough time, and when it was done he had spent enough of himself that he fell into a slumber so deep he might as well have been dead. Dead, but undying, he communicated to the Exiled by walking in their dreams and sending them prophecies while they slept. Telling them to wait, and be patient.
Until now. Now something is wrong. Aelar hardly communicates with us at all, and when he does the prophecies are so weak that only the strongest among us can receive them. And magic, his gift to us, is dying with him faster than ever before. We need to act, and we need to do it soon."