Nasadi was the Queen Consort of the Carja tribe, the wife of Sun-King Jiran and the mother of his youngest son Itamen: Jiran's oldest sons, Kadaman and Avad, are presumed to be the children of Jiran and another woman. During the Liberation, when Jiran sensed the battle was lost, he ordered his champion Helis to take Itamen and Nasadi to Sunfall, an order which Helis dutifully obeyed. At Sunfall, Jiran's loyalists deemed themselves the Carja in Shadow, naming Itamen their Sun-King, although he was little more than a figurehead to Helis and Bahavas. In effect, Nasadi and Itamen were prisoners, forced to comply with the will of the Shadow Carja.
Concerned for Itamen's well-being, Nasadi did everything in her power to protect her son. In one such instance, Helis attempted to make Itamen observe human sacrifice in the Sun-Ring, hoping to train Itamen in the example of his father. When Itamen resisted and turned his gaze, Nasadi quickly intervened, shielding her son from the sight and protecting him from Helis's influence much to Helis' annoyed consternation. Not blind to the suffering of the slaves, Nasadi would occasionally have food from her table brought to the children in Shadowside.
As early as the conclusion of the Liberation, the Carja sent an agent named Vanasha to Sunfall, hoping to smuggle Itamen to Meridian and remove the Shadow Carja's legitimacy. Nasadi confided in Vanasha, who was posing as her handmaiden, that she feared for Itamen, and that they both wanted to defect to Meridian.
In the chaos surrounding Bahavas's death, Vanasha managed to smuggle Nasadi and Itamen out of the palace, escorting them on a route through a gorge to the Branded Shore. The escape did not go unnoticed, however, as the Shadow Carja discovered Itamen's disappearance and sent men after him. Nasadi and Itamen were brought to the waiting barge on the shore while Vanasha, aided by the Nora Brave Aloy and Carja soldiers, eliminated the pursuers. Once the Shadow Carja were eliminated, Nasadi and Itamen were escorted across the lake to Brightmarket, where they were welcomed by Avad and brought to Meridian.