Imagine if a band of angels came down from Heaven to the court of Theodosius and then proceeded to hang out for the foreseeable future. That is the what the Zaian have done in the last few thousand years in regards to the mortal races. The Zaian regard themselves as, and promote the idea that they are, messengers from the great beyond, chosen to convey the word of their God to the lesser species of the World; and they have made the Emperor of Tarsis their vicar.
Zaian are a four-legged species, like the Arkanin. However, they are vertically oriented, rather than horizontally oriented, and stand much taller and much lighter. Climbing and jumping are both things the zaian excel at, though they prefer not to show off their talents. There is little difference between male and female.
Zaian are apparently made of a crystalline substance, what exactly that is or how it came to be so is a closely-guarded secret. This body is much stronger than mineral crystal, and lighter, but crystal remains the best word to describe the unknown material by. In this form, the zaian is essentially immortal. However, there are very few (relatively) long-term zaian appearing in mortal histories. The turnover rate of ambassadors to other Realms is usually one to three centuries; then a new zaian appears and the old one is never seen again. What happens to them is another mystery.
Undergoing rewrite, but the zaian prefer not to speak of their history for the most part. Their story has its true roots in the distant past, but for all purposes, it begins eleven thousand years ago with the first Emperor's reconquest.
At the dawn of the reconquest, there were seven zaian of note: Atheran the High Chronicler, who loved the Tarsins most among his people whom he led, Sedîth, whose heart was coldest to the mortal races, Niren-Sûl the Prophet, spiritual liege of the zaian and father of the New Faith, Tôthara, a frequent emissary, Vanûn-Sîl, war-leader of the zaian, Haianô, a great artisan, and Entarî, the Constructor, a soft-spoken soul known for his oddities by many an Emperor. But fate has claimed them all, except for Entarî, the last living memory of the elder days to walk among mortals. How many of them there once were is a mystery, but it is apparent that their numbers have been thinned greatly, especially by the Age of the Shadow Emperor.
If one desired to contact the zaian, they are known to respond to messages sent to their unmanned post on Ai-Kaion. The true zaian home is popularly thought to reside somewhere secret, perhaps even beyond Coalition territory. Currently, Entarî is de jure leader of the zaian, though he leaves actual decision making to younger individuals, and has no interesting fighting the Earthmen, the Sarthîm being much more of a threat in his eyes. This has not stopped a handful of younger zaian from doing their part for the Nine Realms, however.
The zaian remain the designated messengers of the New Faith, as the Tarsins call it. It was the zaian who brought the teaching to them, and it is the zaian who regulate the main religion of the Nine Realms. Unsurprisingly, the Tarsins and others treat them with great awe and respect. The very presence of a zaian is empowering to the mortal races, who often get the notion in their heads that they are unstoppable with a zaian on their side. And unsurprisingly again, this gets into the heads of young zaian as well; the divine power and reverence the others treat them with is an intoxicating mix, and history shows that this is all it takes to make a zaian into a wrathful, agent of destruction. For this reason, the zaian watch themselves closely, and shun responsibility of power when they can. There is a darkness in their souls, they say, one that must be kept shackled whatever the cost. It is one of the World's great ironies the messengers of Heaven should be tainted so.
For such a prominent and potent force, the zaian are often missing from Coalition affairs. Their entire nature is a secretive one. No mortal has ever been aboard one of their ships, nor seen where they live, nor ever learned the actual name of one. All the names the zaian have were given to them by Tarsins or other aliens that dealt with them. Everything known about the zaian is only what they have deliberately revealed.