In Batman: Death and the Maidens, it is revealed that Ra's al Ghul had a love child born during his travels in Russia in the 18th century named Nyssa. Enamored by the romantic stories that her mother told her about Ra's as a child, Nyssa sets out to find Ra's and eventually locates him at his headquarters in North Africa.
Impressed by her beauty, her warrior skills, and the fact that she was able to locate him, she is promoted to a position similar to that later held by her half-sister, Talia. As a right hand associate, she accompanies him during his adventures. Ra's is so impressed with her abilities, he even allows Nyssa to use his Lazarus Pits. Like her sister Talia, Nyssa eventually becomes disenchanted with Ra's genocidal plans to "cleanse the Earth," and disassociates herself from her father sometime in the early 19th century. Ra's reluctantly approves this, believing that she will return to him and that she and/or her children will become his future heirs. To his disappointment, Nyssa refuses to give herself or her family to him, causing him to disown her permanently. He does however allow her to keep a Lazarus Pit for herself and, much to his surprise, she finds a way to reuse it, allowing her to survive until modern times.
The Second World War
During World War II, Nyssa and her family are sent to a concentration camp, where Nyssa's entire family dies and she is rendered infertile by gruesome Mengele-style experiments. At one point she begs Ra's for help, but he refuses her, stating that, while he does not agree with Hitler's ideas, his cause could only be aided by the millions who will be exterminated by Hitler's scheme.
Death and The Maidens
Broken by her horrifying experiences during this time, and enraged that Ra's has abandoned her and her family to die at the hands of the Nazis, Nyssa is finally motivated to act when her great-grandson - her last living descendent - is killed. She plots to kill Ra's by befriending, kidnapping, and brainwashing Talia and using her to kill Ra's. To this end, she captures Talia and, using a Lazarus Pit, kills and resurrects her in rapid succession, leaving Talia virtually broken from the trauma of dying again and again in so short a time. Rendered apathetic by her time in the camp, unable to feel anything, Nyssa then attempts to destroy all hope and optimism in the world by assassinating Superman with Kryptonite bullets she steals from the Batcave, hoping that, by uniting the world in one moment of tragedy, she will manage to rouse herself once more.
While Batman is successful in preventing the assassination of Superman, he is unable to stop Ra's from being killed by Nyssa. This in turn is part of a greater plan by Ra's to ensure that his daughters, both initially dissatisfied with his plans, will realize that he is right, and that they would come to accept their destinies as his heirs. Realizing and accepting this, both Nyssa and Talia become the heads of the League of Assassins. Talia disavows her love for Bruce Wayne, and both sisters declare Batman to be their enemy, Nyssa promising that she will not fail her father as Batman departs.
Nyssa is in possession of the world's last Lazarus Pit, which has granted her longevity and the ability to heal her wounds; she survives The Holocaust thanks to its powers. She is also extremely wealthy, especially since she assumes control of Ra's's organization and joins forces with Talia. Like her father and sister, she knows Batman's secret identity and the location of the Batcave.
During Infinite Crisis, Nyssa and her sister connive to use Talia's membership in Luthor's Secret Society of Super Villains in order to take over the planet. Nyssa tries to recruit Batgirl to stand at her side as "The One Who Is All". She attempts to explain why she is working with the villains of the Society to Batgirl: Template:Cquote
Cassandra refuses, and, along with Mr. Freeze, escapes from Nyssa's grasp.
In Robin #148, the first One Year Later issue, Nyssa is seen in Northern Africa, planning an unknown plot with two terrorists. As she gets into her car to leave, it explodes. In the following issue, Lady Shiva reports that Nyssa Raatko is dead, probably killed by the League of Assassins.