The Nightsister lair, alternatively called the Nightsister fortress, was a stone-constructed stronghold situated on the planet of Dathomir, functioning as the base of operations for the Force-sensitive Nightsisters. Subsequent to the Nightsisters' annihilation during the Battle of Dathomir, the fortress remained unoccupied until Maul established it as his headquarters during the Imperial Era.
Following Asajj Ventress's survival of Dooku's assassination attempt against her on Sullust, she made her way back to Dathomir, landing just outside the fortress. Subsequently, she was escorted to the village and received medical assistance from Mother Talzin and her Nightsisters, after which she initiated an assassination attempt targeting the Count.
Shortly thereafter, Dooku arrived at the village to accept Talzin's proposition of a new apprentice. However, Talzin intended to use the offer as a guise to kill Dooku. Ventress then departed to locate a worthy Nightbrother to serve as her instrument. Ventress then came back accompanied by Savage Opress, who had been transformed into a monstrous warrior. The other Nightsisters then presented his brother, Feral, and commanded Opress to execute him. Opress complied without hesitation and was subsequently taken to Dooku.
Jedi Master Obi-Wan Kenobi and Jedi Knight Anakin Skywalker then journeyed to the fortress, where Talzin revealed the name and location of the Nightbrother they were seeking. Following the Jedi's meeting, Opress returned to the village, where Talzin healed him and dispatched him on a mission to locate his brother Maul.
Ventress then returned and underwent baptism and induction into the Nightsisters. However, Dooku and Sidious subsequently dispatched General Grievous to wipe out the Nightsisters. Initially, Ventress, the Nightsisters, and Old Daka's Army of the Dead managed to resist Grievous's army of battle droids. Talzin, within a Hidden Cave, then employed her magick to inflict torture upon Dooku, threatening to end his life if he did not cease the attack. Grievous, following the green mist, then disrupted Daka's and Talzin's magic. Although the Nightsisters were annihilated and their fortress was left in ruins, both Talzin and Ventress survived.
Talzin remained within the devastated village, utilizing her magicks to monitor Opress's advancement in his quest. He returned with Maul shortly thereafter, and Talzin guided the two brothers to the altar, where she employed her magick and components of super battle droids to mend Maul's fractured mind and body. Subsequently, Talzin disappeared.
Approximately a few months before the war's conclusion, Asajj Ventress escorted Quinlan Vos to Dathomir with the intention of instructing him in the ways of the dark side, with the belief that it would aid him in their mission to assassinate Dooku. She guided the Jedi Master into the dilapidated village during a training duel, then tasked him with eliminating the Sleeper creature residing in the village's waters. Vos successfully accomplished this, albeit with some difficulty. Their mission failed, and Ventress ultimately sacrificed herself to protect Vos. Her remains were returned to the village's waters, where she had been baptized, and she was greeted by the voices of her deceased sisters.
Following the establishment of the Galactic Empire, Maul took up residence in the Nightsisters' former lair, where he amassed a collection of mementos from his experiences during the Clone Wars, including the Darksaber and a portrait of the Duchess Satine Kryze. Maul's ultimate objective was to ascertain the whereabouts of his longtime adversary, Jedi Master Obi-Wan Kenobi, by retrieving the remaining fragments of the holocron's visions from Bridger's mind. Maul brought Bridger into his lair after the latter consented to accompany him to Dathomir in order to safeguard the location of Chopper Base.
When Bridger noticed the Darksaber, Maul admonished him for touching it and informed him that his Mandalorian friend Sabine Wren could provide a better explanation of the artifact's history. In a ritual intended to complete their shared vision, Maul and Bridger consumed a magick potion that caused their eyes to glow bright green and emit beams of light into a cloud. Consequently, Maul discerned that Kenobi was concealing himself on a planet with twin suns. Bridger learned that Kenobi possessed the key to destroying the Sith. Following the ritual, the spirits of deceased Nightsisters materialized, demanding that the two pay a price of flesh and blood.
Maul and Bridger attempted to escape, but Kanan Jarrus and Wren then entered the cave, having tracked Bridger's wrist comm. Following an exchange of gunfire, the spirits took possession of Jarrus and Wren's bodies. The possessed Jarrus and Wren then launched an attack on Maul and Bridger. However, they succeeded in reaching the cave's entrance. Given that the altar served as the source of their power, the spirits were unable to exit the cave. Having achieved his goal, Maul then prepared to depart on his ship Nightbrother and extended an offer to take Bridger as his Sith apprentice. However, Bridger declined to abandon his friends, and the two parted ways.
Bridger returned to the cave with the intention of exorcising his friends. He encountered Wren and managed to exorcise her by pushing her outside, causing the spirit to depart from her. Bridger then discovered Jarrus sitting atop the altar. He then proposed to trade his body in exchange for the Nightsister spirits releasing his master's body. The spirits consented, contingent upon Bridger defeating Jarrus in combat. After defeating Jarrus, the spirits released him. Bridger then wielded the Darksaber and his green lightsaber to destroy the altar, causing the spirits to vanish. Subsequently, Bridger informed Jarrus and Wren that Kenobi held the key to destroying the Sith. Resolving to prevent Maul from killing Kenobi, Wren claimed the Darksaber.