The Raya Lucaria Grand Library is one of the highest points in the Academy of Raya Lucaria located in Liurnia of the Lakes. It is where Queen Rennala was sequestered following her abandonment by Radagon and the subsequent civil war between the sorcerers of the academy.
Here, Rennala cradles the Great Rune of The Unborn nestled in an amber egg, the farewell present from Radagon, and attempts to perfect her art of rebirth. She is surrounded by many imperfect creations, dubbed her "sweetings."
Sellen and Witch-Hunter Jerren will have their final confrontation here, depending on who the Tarnished sides with, either Jerren will remain outside or Sellen will take her place in the inside where she may continue to sell the Tarnished any glintstone sorceries.
There is a single chest in the library, which is locked by the Discarded Palace Key. Within is the Dark Moon Ring needed to complete Ranni's questline and unlock the Cathedral of Manus Celes.