Mass Effect: Revelation Edit
It was one of Had'dah's scout teams, searching dangerously close to geth space, who discovered a mysterious artifact in 2162. Had'dah visited the discovery site somewhere after 2162 and recognized its potential. Unbeknownst to him, however, he also became subtly indoctrinated, urging him to uncover any secrets the artifact had. Searching for the best expert available to unlock its secrets, he was irritated to discover that the man he needed was a human, Dr. Shu Qian. However, the effects of indoctrination made him set aside any hatred of humans, and Dr. Qian began working on the artifact in earnest from his lab on Sidon, but maintaining close contact with Had'dah.
In 2165, after Kahlee Sanders threatened to expose Dr. Qian, Had'ah hires the Blue Suns to attack the Sidon facility and cover up any evidence of Dr. Qian's defection. He is forced to hire a krogan bounty hunter named Skarr to find and kill Sanders. Had'dah tries to intimidate Skarr, but is shocked by the level of intelligence and biotic power the krogan possesses, and eventually agrees to a larger payout. When Skarr fails, Had'dah orders him to destroy the Dah'tan Manufacturing facility, the only remaining link between Had'dah and the events at Sidon. He later sends the krogan to capture Kahlee to help Dr. Qian work on the artifact.
A Dah'tan worker survives the attack on the facility long enough to be able to point Saren Arterius, a Spectre, Had'dah's way. Saren then attacks the eezo refinery on Camala where Had'dah and Dr. Qian are holed up. When confronted by the Spectre, Had'dah claims that Dr. Qian's obsession with the research has turned him into a liability. After Saren kills Dr. Qian, Had'dah determinedly bargains for his life, arguing that if Saren wanted to unlock the secrets of the artifact, he would need Had'dah's help and resources – otherwise he'd have to begin the research all over again, delaying the process by years. Saren responds by telling Had'dah that he is a patient man who doesn't mind waiting, then shoots him dead.