The Altar of Mortis, situated within a cavern on the otherworldly planet Mortis found in Wild Space, served as the repository for the Dagger of Mortis. This altar resided in a cavern deep below, accessible via a staircase, and was encircled by a fiery green luminescence. Crossing this aura was necessary to obtain the mystical weapon. Its design intentionally prevented specific members of the resident Force wielders' family, known as the "Overlords" or "The Ones," from acquiring the dagger.
Following the enticement of the Chosen One, Anakin Skywalker, to Mortis, the Force wielder called the Father was double-crossed by his offspring, the Son. To thwart the Son, the Daughter escorted Obi-Wan Kenobi to the Altar, explaining that while she could proceed no further, he possessed the ability to retrieve the Dagger and halt the Son's actions.
Once the weapon manifested before the Jedi Master, Kenobi attempted to deliver it to Skywalker. However, the dagger was snatched by his Padawan, Ahsoka Tano, who had fallen under the Son's sway. Subsequently, the Son secured command of the dagger and inadvertently killed the Daughter. The Father then directed the dagger toward himself, leaving the Son sufficiently exposed for Skywalker to ultimately defeat him. Consequently, equilibrium in the Force was reinstated on Mortis. However, a radiant white light emanating from the Father's monastery caused the entire realm to vanish.