The Deeplord of Xilvalur, Teralis Yllaralei was a figure of utter mystery, even to those within their crownland. They did not rule with a firm hand, only acting when needed to defend their Elven subjects from the horrors of the Sea of Trees. Often called "Teralis the Evergreen", they were undoubtedly the most powerful Archdruid in the known world, and had lived for eons.
Possessing both a temperament and form that constantly fluctuated, Teralis was considered by religious scholars to be the closest living embodiment to true freedom. Using druidic powers to harmoniously change their form with their emotions and often did not stay in a singular space, though were supposed to occupy the Tree of Teralis. However, as if blessed with premonition, Teralis always appeared to fight whenever Tirion Isilmírë was in danger.
When presenting themselves as a true wood elf, Teralis appeared thin and extremely tall, with flourishes of flora and fauna accenting their reedy form. They had been involved in many of Somnum's greatest works; evidence of this could be seen in their possession of the Lûthloth Mîr, given to them before the Age of Giants by the Azure Paragon. As Teralis wished to protect their woods without always being their, they gifted the Epochal Artifact to their people, who used it to defend Xilvalur for countless generations.
As one of the oldest mortals living in Head of the Greatwyrm, they were often relied upon to tell of lost histories, but their answers tended to be floaty, cryptic, or downright unconsidered. This floatiness caused difficulties in diplomatic relations with the Elthysi Sovereign and their counterpart queendom Ardhon Miniel, but such politicking was seemingly unimportant to them.