A powerful magically enchanted spirit that resided within the Crystal Castle that was situated on top of the mountain Skydancer on the planet Etheria. This ancient being served the forces of good and was privy to secrets from the times of the First Ones who were the founders of Etheria. During its time as the keeper of the Crystal Castle, Light Hope met with Agho; King of the Trolls who had journeyed to find it. During their time together, Light Hope asked Agho to keep the location of the Crystal Castle a secret to which the Troll King gave his word. In later years, Castle Bright Moon faced a terrible attack from the Evil Horde leading to She-Ra going on a quest to find the Crystal Castle. Through a riddle given by Agho, she managed to find the Castle and Light Hope allowed her entry whilst stating that it had long awaited her arrival. Manifesting itself as a colossal pillar of light and told her of one way to save Bright Moon from Shadow Weaver's attack. Namely the Great Clock at the center of Etheria which could speed up time to allow the moons to move past the eclipse and fill Queen Angela with their power.
Light Hope was responsible for transporting She-Ra to Etheria's center but not before warning her of the protectors of the Great Clock. Once there, she managed to succeed in her quest which in turn defeated the Horde's planned destruction of Castle Bright Moon. Afterwards, She-Ra met with Light Hope who asked her to also keep the location of the Crystal Castle a secret. Furthermore, it asked her to treat the Castle as her haven and that She-Ra should visit it more often to which she agreed thus leading to her becoming the defender of the Crystal Castle.