Tales of Phantasia: Narikiri Dungeon X sets place in the year 4408, 104 years after the end of Tales of Phantasia. The story begins lone fairy Etos wandered around the world, in search for her friends. However, after long time of journeying, still, none of her friends were to be found. And slowly, the fairy lost her power. Appearing before the weakening fairy was a mysterious woman named Norn who nurses her, but for a price. Norn then gives Etos the responsibility of taking care of two infants named Dios and Mell. Etos takes care of the children and life was peaceful, Etos was a wonderful parent figure for the two. However thirteen years later Norn sends her messenger, Albert to give the two the power of Narikiri. Tragedy strikes when Vahalla City is attacked by mysterious force. Dio and Mell have no choice, but to collect the essences of the summon spirits of Aselia to stop this terrible power.