The Lake of Apparitions was a body of water situated within a realm of the Force called beyond shadows. Individuals traversing this Lake had to be extremely cautious, because missteps would cause them to plunge into the Depths of Eternity, a place of no return. As one walked upon it, the spirits of dead Force-sensitive individuals manifested on the water's surface, an effect known as the Mirror of Remembrance. Thick fogs, referred to as the Mists of Forgetfulness, perpetually shrouded the Lake. Mara Jade Skywalker's spirit in the Lake of Apparitions During their quest to understand what drove Jacen Solo to embrace the dark side of the Force and become Darth Caedus, Luke Skywalker and his son Ben journeyed to the Maw. There, they discovered Sinkhole Station, a compact space station reminiscent of Centerpoint Station, which served as the home of the Mind Walkers—Force-sensitives with the ability to separate their consciousness from their bodies to explore beyond shadows. Luke and Ben, accompanied by the Mind Walkers, ventured beyond shadows and arrived at the Lake of Apparitions, where they communicated with the spirits of Anakin Solo, Mara Jade Skywalker, and a now-peaceful Jacen Solo.
Later, after arriving on Abeloth's world on a mission with the Lost Tribe of Sith aimed at eliminating Abeloth, the Skywalkers came to the realization that each location they had witnessed beyond shadows corresponded to a real place on the planet. On Abeloth's native world, the Skywalkers utilized Mind Walking alongside Sith High Lord Sarasu Taalon, Sith Saber Gavar Khai, and Captain Leeha Faal, and once again found themselves at the Lake of Apparitions. In that location, both the Jedi and Sith encountered numerous deceased companions. Skywalker once more saw and briefly conversed with his wife. However, Faal also encountered some of her deceased adversaries, who pulled her into the Depths of Eternity, resulting in her death.
Skywalker would eventually return to duel Abeloth again during the Liberation of Coruscant, where he received assistance from Darth Krayt. At the time, Krayt's identity, beyond being a Sith Lord not from the Lost Tribe, remained a mystery to Skywalker. Skywalker's deceased wife also offered help, and together they managed to, albeit temporarily, defeat Abeloth.