Curare was originally a monk in the Himalayas. As a child, she bared witness to the coming of the eventual Green Lantern: Kai-Ro. Kai-Ro was discovered by a monk and brought to the ashram. Curare and Kai-Ro grew up together as surrogate siblings unfortunately, their views on life differed. Kai-Ro was happy with his life at the ashram but Curare viewed the temple as a cage and the monk elders as her keepers. Curare believed there was a life beyond the ashram that offered riches and recognition. Kai-Ro only wanted to practice humility and was content with the life he had at the temple.
The time had come to choose the next Dalai Lama. Buddhists from three other monasteries and secular clergies attended this momentous event. It was originally a tradition to have one of the elders choose a name from a golden urn left by Buddha and that name chosen would become the next Dalai Lama. However, the monks decided to go with a different tradition. A table of items was placed in front of Kai-Ro. One item belonged to the original Dalai Lama while the rest of the items did not. It was up to Kai-Ro to choose the right item. If he chooses correctly then Kai-Ro will be deemed the reincarnated soul of the former Dalai Lama.
Among the items was a Green Lantern ring (unknown to whom it belonged to originally) and the ring immediately activated as Kai-Ro moved his hand closer to the table. Kai-Ro was chosen to become the new Green Lantern of Sector 2814. The monks were astonished as well as frightened by the great power that Kai-Ro now wielded. Curare takes advantage of the moment by proclaiming that Kai-Ro has failed the test and now the monks must choose the Dalai Lama successor by picking a name from the golden urn. For some odd reason, the ring sensed deceit in Curare's soul and destroyed the urn to expose her true nature. When the urn shattered, it became apparent to the monks that the original sticks that bared different names were all replaced by sticks with only Curare's name etched on them.
The monks decided to banish both Kai-Ro and Curare from the ashram. The monks were disappointed with Curare's act of deception with the urn but more so by her refusal to accept the teachings of Buddha. As for Kai-Ro, he was excommunicated because he now holds a great power that could tempt him to abuse it. Curare believed it was Kai-Ro who actually made her plan fall apart and not the ring. Kai-Ro expresses his pity that Curare can't see past her own blind ambitions and hatred. Curare swears to Kai-Ro that the next time they meet, it will be not as siblings but as enemies.
Later on, Curaré undergoes a process performed by a dark monastery which causes her skin to develop a blue pigmentation. It is believed that this process caused some kind of facial disfigurement because Curare decides to conceal her face after suffering the transformation. Curare goes on to became the greatest assassin within the League. Curare met the new Batman of Gotham when he foiled her attempts to kill DA Sam Young. After her failure to kill the district attorney, Curaré becomes a target of the League. However, the League underestimates the tenacity of Curare and one by one, each member of the League is dispatched. Curare was eventually apprehended by Terry McGinnis but she escaped custody and decided to reestablish the League of Assassins.
She possesses an amazing degree of agility and endurance. She was able to leap of a building onto a moving train without flinching. She has great knowledge about poisons as shown in her second appearance in the Batman Beyond cartoon. As she used poison on her victims to cause them to be completely paralyzed with no sentient mind, or as a policeman said
'the lights are on but no one is home'
. Her weapon of choice is a scimitar, just a few molecules thin at the end of the blade which causes it to slice through most objects with ease. As shown by her cutting a circle in a 10 inch thick steel door without any problems.