Eyir

Eyir is a titanic watcher val'kyr and the leader of the Valarjar val'kyr, notably charged with finding glorious combatants to ascend to the Halls of Valor. Ascended vrykul shieldmaidens of the Valkyra battle to prove their worth to Eyir and become val'kyr in order to serve eternally in the Halls of Valor.

Ashildir called her goddess. Eyir has some sort of history with Bwonsamdi, and it does not seem to be a positive one.

Background
Sylvanas Windrunner attempted to subjugate her in the Vault of Eyir with the Soulcage, a magical lantern granted by Helya as part of the secret deal they made in Helheim, but Genn Greymane smashed the lantern and freed her.

In the Halls of Valor, Eyir granted Hyrja her blessing and transformed her into a val'kyr, after which she watched her fight the class orders. Eyir was also present during the Trial of Valor alongside Odyn.

Archmage Kalec and a champion were granted passage into the Vault of Eyir by Ashildir in order to receive Eyir's blessing, which they obtained because they impressed Odyn.

Legionfall
Sigryn, the daughter of God-King Skovald, went to the Vault of Eyir to take her place as rightful heir to the throne of the Tideskorn. Eyir had foreseen Sigryn's destiny and set her on the path to unifying the Tideskorn. When Sigryn found her brother Torvald whom she thought dead, he told her of what had happened that night when her family was assaulted by assassins. Asking Eyir to explain her the truth, she revealed that it was Odyn who had sent the assassins that fateful night, for an ancient Valkyra prophecy foretold that she would bring ruins to the vrykul, as described in the Scrolls of the Faldrottin. Sigryn, overwhelmed with anger, lost control of the fel inside her, which her father Skovald had fed her when she was younger, and stormed the Halls of Valor. She regained her senses thanks to an adventurer and asked Eyir to judge her. Instead of punishing her, the val'kyr asked her to take on the burden of becoming God-Queen of the Tideskorn for her strength of will, as she proved to be the only vrykul to overcome the fel. Sigryn accepted.

Battle for Azeroth
Vol'jin, the late Warchief of the Horde, sought to find out who it was that had told him on his deathbed to name Sylvanas the new warchief. He had come to believe it was not the loa that did so, but in fact something darker and stronger. Vol'jin, Baine Bloodhoof, Talanji, and a Horde adventurer traveled to Stormheim to confront Eyir about it. Val'kyr guards initially held them off believing they were minions of Sylvanas, but even after the guards were slain Eyir sensed the presence of Bwonsamdi, loa of death on Talanji and refused to allow her entry. She informed the group that Vol'jin's return was not her doing; Vol'jin had been "touched by the hand of valor" and become something beyond even her power to forge. She went on to say that whoever it was that had aided him was not the same person who had told him to make Sylvanas warchief. With that being all that she was willing to share, Eyir commanded them to leave and never return.

Quests

 * The Gates Are Closed
 * The Reluctant Queen
 * To Silence the Bonespeakers
 * Unanswered Questions

Objective of

 * A New Life for Undeath
 * The Mark

Trivia

 * Eyir is voiced by Erin Fitzgerald.

Speculation
Eyir likely replaced Helya as leader of the val'kyr after the latter betrayed Odyn.