Maybe oryx was the first of his kind to come into existence, the darkness first creation his champion. The hive see him as God for his power, and that for he was the first hive to walk this world.

The best way to think about Oryx, in my opinion, is to think Greek. In the beginning there was chaos, the void, from which came many powerful beings. To name 3 Alpha Lupi (the Traveler) Oryx and the Darkness. Possibly also the Nine, but I doubt that. From this I believe she reproduced asexually by using the Hive magics and her own blood. Yes, I said she and her, I'll touch on that after. She first created her initial spawn, the only one we know for sure is Crota, but other likely members include Xol Yul Ur and Eir. Now back to the she. As shown in the rusted lands grimoire, the wizards are actually the superior beings in the Hive. They also lead the use of magics which would, as I suggest, be necessary to reproduce.

No theory about oryx can be taken as truth, not even a half truth, in some cases. Osiris is the only being with as much knowledge as to rival toland, but both are lost. Oryx could be any number of theories, but how do we know until we face the god and lay him low. The only thing that is certain is that oryx is coming, this irrefutable. We can slow him, hold off his forces, but unless the traveler is healed, we will only be putting off a great disaster than we met on the moon, and by the time it this disaster comes, a new generation of guardians may be left to face. (All that above is for story sake) These are simply thoughts are oryx, and potentially, the great darkness. Lastly,"there's a wizard here."

It is said as "Crota son of Oryx" not in a literal meaning of son but perhaps a commander of Oryx or even little lower than that, tons of answers are viable and theories with a strong estimate in the educated guesses and theories, Can only be translated through the grimo ire we have now

Oryx being an opposite of the traveler would make perfect sense. Oryx is a god to the hive like the traveler is to the guardians.Oryx motive is to spread darkness, but he can't with the travelers influence on the dimension. This gives Oryx a motive to destroy the traveler, but in order to do that, he must physically animate himself in order to lead his army to spread darkness. This is how "Crota Son of Oryx" was born, piece of Oryx in the inbodiment of a knight. This would make so much sense because Crota's soul looks like a shard, a shard of Oryx, and when activated it summons Crota.

In traditional thinking, it's easy to assume oryx would be some sort of ascended hive knight or at least bound to some physical form like crota was when we finally brought him down. However Oryx may be more of an idea, a being who is powerful enough to maybe be within a more ethereal form and through hive magic twist space to create hive and their powers, but as we've seen it seems limited because crota was defeatable. Besides, Oryx was already stated to be not the strongest. Maybe he represents one of 5 things the hive reveres or follows during their blighted crusades