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He proceeded to hire an unknown group of individuals to find the Administrator and recover the Australium. He discovered it empty, and deduced that the Australium had been stolen by the Administrator after finding a cigarette left behind at the safe. In desperation, Gray uncovered Mann Co.'s safe of Australium.
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Six months later, Gray's Australium-fueled Life Extender Machine began to run low. Unwilling to fight a child, Saxton Hale conceded, giving up control of the company to Olivia. if they beat Mann Co.'s CEO in unarmed combat, in order to pit Saxton Hale against his daughter, Olivia. Challenge policy, which stated that the CEO of any company could legally seize control of Mann Co. In 1972, Gray surrendered the war to Saxton Hale, acknowledging that his war had turned into a stalemate reminiscent of the Gravel War between his brothers. Saxton Hale rehired the mercenaries, who had been fired from BLU and RED after the takeover, to defend these factories from the robots. facilities all over the world as shown in A Fate Worse Than Chess. Gray created an army of robots to destroy Mann Co. After luring them to a fake meeting using forged letters from each other offering a truce, he assassinated his twin brothers Blutarch and Redmond Mann to take control of their respective companies and absorb them into Gray Gravel Co. In 1971, Gray resurfaced, revealing that, like his brothers, he possessed a life-extending machine, albeit a more efficient and compact version mounted on his back. According to Zephaniah Mann, in 1849, Gray Mann had threatened to blackmail him for his cache of "miracle" gravel.
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After being raised by his eagle abductor, Gray killed and ate her and her children before crawling back to civilization to build his corporate empire, Gray Gravel Company. Disgusted by how he could talk, Zepheniah Mann was going to smother Gray, but before his father could do so, Gray was abducted by a wild eagle and raised as one of its own. He could speak perfectly by the time he was born, but was the weakest physically. The smallest of the three Mann brothers, Gray was also the most intelligent of the three.
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