M-5 Phalanx, Disciple, M-9 Tempest, Biotics
Mass Effect 2
Asari Justicar, Helping Commander Shepard.
Unknown, likely 100s of years
Defeated by Shaak-Ti.
Like many asari, Samara's Maiden phase of life was marked by adventure and excitement. At one point she ran with a mercenary gang and discovered her talent for combat. Her membership in the gang came to an end when she led a transport mission and discovered the cargo was not weaponry or machinery, but slaves intended for sale to the Collectors. Samara tried to have the ship turned around, but met with resistance from her team and was forced to kill them. The Collector ship arrived just as the battle ended; fortunately, the ship was close enough to a mass relay for her to escape. Once safe, Samara gave the slaves a speech about self-defense and passed out the credits, weapons, and armor that had belonged to her mercenary comrades, then left them all at the Citadel.
Samara left her mercenary career after that and slowed down, eventually finding stability with an asari mate and raising a family. Samara had three daughters, but discovered, to her horror, they were all Ardat-Yakshi, suffering a genetic condition that made them kill their mates during melding. As Samara explains later, she herself is a pureblood; she believes that the stigma against them lies partially in their increased probability of giving birth to Ardat-Yakshi daughters.
Two of Samara's daughters, Falere and Rila, chose to live their lives in isolation and comfort. Her third daughter, Morinth, whom Samara described as the "smartest and bravest" of the three, refused to go into seclusion and fled, beginning a spree of murder and violence. Recognizing her daughter's growing addiction to killing her mates, Samara gave up her worldly possessions, swore herself to the Code, and became a justicar.
Samara hunted her daughter across the galaxy for centuries. At one time, Samara had discovered Morinth had perverted an entire village, making them worship her and bringing her young asari as sacrifices. When Samara arrived, Morinth fled, throwing waves of her minions at her and buying herself time to escape with their lives. When Samara was done only small children remained, who she left in the care of the authorities and continued her pursuit. At another time, Samara crossed paths with Nihlus Kryik after she witnessed him murder an unarmed civilian. She had no choice but to engage him. They fought for days on the planet, chasing each other in the wilderness. Eventually, Nihlus manipulated Samara by putting her in a situation where she had to let an innocent die or let him escape. Despite having lost to him, she was impressed that he had learned how to turn the Code against her and adapt.
By 2185, Samara had hunted Morinth out of asari space to Illium. Following a lead that Eclipse mercenaries had helped Morinth escape off world, Samara hunted them down and interrogated one of the mercenaries for the name of the ship Morinth was travelling on. When the merc refused to answer, Samara killed her only to meet Commander Shepard, who had come to Illium in the hope of recruiting Samara. She expressed interest in Shepard's mission, but was required to go into Detective Anaya's custody for a time.
Samara asked Shepard's help in finding the name of the ship—a task made all the more urgent by the fact that, after a day in custody, the Justicar Code would oblige Samara to escape, possibly killing many police officers in the process. When Shepard returned with the ship's name — the AML Demeter — Samara swore the Third Oath of Subsumation, binding herself to Shepard's morals, and vowing to fight the Collectors. However, her hunt for Morinth remained utmost in her mind.
(From Mass Effect Wiki)