Sildëyuir Sildëyuir is a region of the Feywild that is conterminous with the Yuirwood in Faerûn , perhaps two to three hundred miles from end to end . It is the home of the reclusive star , or mithral , elves , who constructed the realm nearly two thousand years ago by breaking it off from the Feywild and turning it into a demiplane of finite size . However , as a consequence of the Spellplague that erupted in 1385 DR , Sildëyuir has been rejoined with the Feywild . The plane has many of the same features and hills as the Yuirwood , and its borders match those of the Faerûnian forest . Sildëyuir is covered with dells with silver - boled trees and streams . Its forests are not as dense as the Yuirwood ’ s , and its trees are taller and more majestic with very little undergrowth . Phosphorescent grow on the silver - trunked trees , and unlike the humidity of the Yuirwood , the air of Sildëyuir is cool . At the borders of the demiplane , the forest grows thicker and thicker , and any track one follows or makes simply bends back on itself . Sildëyuir is in perpetual twilight . The sky in the distance above the crowns of the trees is a soft pearl - gray , and it seems as if there is no east or west , for the same source - less illumination lights the horizon no matter in what direction one looks . Near the sky ’ s zenith , however , the skies are the purple velvet of true night and are filled with preternaturally brilliant stars . During the “ night , ” the sky darkens into pure blackness . Time is slower in Sildëyuir ; two days or years on the Material Plane is about one day or year in Sildëyuir . Sildëyuir can be accessed by circles of ancient stone built by the star elves which serve as portal s from the Yuirwood , and vice versa . Sildëyuir is not connected to the Ethereal and Shadow Planes , although it is linked to the Astral Plane . Sildëyuir is a relatively quiet place . There are a few animals such as white owls , silver - gray deer , black squirrels , large gray - furred bears , and foot - long emerald and sapphire dragonflies . The star elves , masters of song magic and the lords of the realm , live in elegant citadels of glass and pale white stone . They are a peaceful people , and their demiplane is a closely guarded secret , unknown even to most elves . The star elf population has been dwindling for centuries . They once had true cities long ago , but with the entire plane to themselves , they never saw a need to crowd together , so their keeps , towers , and small towns are separated by great distances , and several citadels are abandoned . For several centuries , Sildëyuir has been slowly invaded by strange sorcerer s from the Ethereal Plane called nilshai . They haunt the lonelier stretches of the forests , creating portals to their own realm that exude sluggish , silver - gray mists . The gray mists mark the border of a creeping blight . Beyond them , Sildëyuir is tainted and corrupted . The trees are dead and rotting , and thick , oily black moss grows everywhere . The silver starlight in these areas is gone , and the sky is black . The air is humid and stinks of overpowering rot . The blight essentially transforms the land into a pallid , festering jungle . There are huge , rotting toadstools that emanate a sickly green phosphorescence , and bulging , fluid - filled fungi hang from the rotting trees . The nilshai also loose monsters in the forests . Recently , the nilshai invasion has gotten worse . The nilshai now occupy citadels that were recently occupied by star elves , the former residents mysteriously vanishing . Some star elves are now considering leaving Sildëyuir and returning to the Yuirwood , while others advise seeking help from Aglarond and beyond . The Evermeet ian sun elf Araevin Teshurr , now Grand Mage of the reestablished Myth Drannor , has promised to aid the star elves , and the high mages of Evermeet are considering to help . History . In −9800 DR , the Yuirwood was settled by green elves in the aftermath of the Crown Wars . In −6950 DR , the star elves began leaving other elven nations and gathering in the Yuirwood . In −6600 DR , the star and green elves founded the realm of Yuireshanyaar in the Yuirwood . The human empire of Unther battled Yuireshanyaar in −1250 DR for control of the southern Aglarondan coast , and the Yuir were driven back into the woods . From −1076 DR to −1069 DR , the Orcgate Wars occurred after an Imaskari wizard opened up a gate in Mulhorand to the orc ’ s home world , and Yuireshanyaar was pressed hard by the orcs . Faced with the encroaching humans along the Wizard ’ s Reach ( most from Old Unther ) , the star elf High Mages of Yuireshanyaar created a forest - wide network of stone circles and worked a mighty high magic spell through the stone menhirs to construct the extraplanar world of Sildëyuir from −900 DR to −600 DR . In −699 DR , the Year of Moon Blades Crashing , the star elves completely abandoned Yuireshanyaar for Sildëyuir , but many wild , or green , elves chose to remain in the Yuirwood . Araevin Teshurr and his companions visited Sildëyuir in 1374 DR , the Year of Lightning Storms . The Twilight Tomb . Centuries ago , a star elf wizard named Mourel Duskwalker tried to seize control of all of Sildëyuir . He marshaled evil forces against the main star elf city and was eventually defeated . His body and remaining life force were sealed in his glass citadel , which was then removed from Sildëyuir and became a “ loose ” piece of the demiplane . Unbeknownst to the star elves , Mourel ’ s citadel has a portal that is connected to the Yuirwood . The nilshai sorcerer Tolg ’ byri discovered this portal and used the citadel as a base of operations for gathering an army to conquer Sildëyuir , which has awakened the spirits of Mourel and his followers . Tolg ’ byri was betrayed , and now his army is led by a supposed half - orc named Savera , whose true identity is unknown to “ his ” followers .