I would hazard to guess that Azem became Hydaelyn's chosen almost immediately after the fracture. Something of a final wish, a wanting almost, by Venat in their final moments before the summoning was carried out, made manifest by Hydaelyn.
I also have to ask. Was Venat (the T is silent right?) the Nhamaa to Azem's Azim? Without going into bad fanfiction of course, what could the possible connection be between that legend to the "real events" of the final days?
Hien: Aye. I would know more of the Oronir─of their creation, and of Father Azim.
Udutai: As you wish. Come, let us sit.
Udutai: Before we begin, tell me: what do you know of the Au Ra, and how they came to be?
[“In the days before men, Azim and Nhaama waged a bitter war…”]
Udutai: Yes, yes. A common tale, and one believed by many tribes.
Udutai: But what it does not mention is this: Azim and Nhaama were lovers.
Udutai: Oh, they fought in the beginning, as did their creations. That much is true. But when they saw how the Xaela and the Raen rose above their hatreds and joined hands in harmony, their hearts stirred, and the love their children shared became theirs as well.
Udutai: Alas, he was of the sun and she of the moon. Apart they must remain, lest day and night cease to be, and with them all creation.
Udutai: With sadness in their hearts they returned to the heavens─he to the day, she to the night, destined to walk before and after, never to meet.
Udutai: As time passed, Azim’s yearning for his beloved grew deeper still. Was there truly naught that could be done, he wondered. At last, he knew.
Udutai: “If the Father cannot be with the Mother, then he shall go amongst her children. Now and ever after.“
Udutai: So it was that Azim took a fragment of his being and with it fashioned an avatar. Clad in scale of midnight, he descended, and sought out the Xaela.
Udutai: Yea, he was the first Oronir. We are of his flesh and his blood. We are the children of Azim, and it is our duty to watch over and keep the Xaela safe.
Hien: …I confess, I did not expect the tale of your people’s beginnings to be quite so romantic.
Hien: Yet I must ask: if it is your duty to defend the Xaela, how can you go to war with them in the Naadam? Is that not a contradiction?
Udutai: If a father disciplines his son, does that mean there is no love in his heart? Xaela are not wont to kneel. They must be made to─only then will they heed reason.
Hien: I see… Such is the way of the Steppe.
Hien: Thank you, elder, for sharing with us your wisdom.