According to Wowhead's summary of each of classic gold wow the covenants, the Kyrian have been"tasked with shuttling spirits between the lands of the living and the dead". If you want a way more comprehensive guide to everything that the Kyrian Covenant offers, Wowhead has you covered there,

Just inject World of Warcraft: Shadowlands into my veins

However, a lot of angels shepherding the spirits of the dead to where they belong in the Shadowlands is pretty much precisely what I expected from a minumum of one of those covenants in Shadowlands, therefore what pulled me was that characters were chosen to illustrate the covenant's purpose.

Blizzard centered the debut to the Kyrian covenant around Uther the Lightbringer, who's among the most significant characters in all of Warcraft.

In the cartoon, Uther's soul arrives on the doorstep of the Kyrian at Bastion, as there's some kind of afterlife sorting system which places souls where they belong in the Shadowlands. However, Uther can not let go of his life, and he thirsts for justice. He is chastised for it for a while before Devos, the Paragon watching over him, finds that his soul is injured from Frostmourne, the Lich King's blade

Now, I could probably enter super-deep detail about why some of the matters, but I'll save myself the effort, and also you the agony of digging through it. What's that the runes on Frostmourne are seemingly from the Maw, an area of the Shadowlands where only the most wicked, irredeemable spirits are cast. And, Arthas, who has caused so much harm, by seemingly channeling the power of the maw, was throw into buy wow classic gold this evil place from the spirit of his youth teacher who expired with his blade.