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Cyrell was revived by his Ghost, who he named Strain, in a forgotten valley on the edges of Mercury that had escaped the Vex's terraforming. Although he became friends with Strain, Cyrell felt burdened by his role as a Guardian and told his Ghost that although he had no memory of it, he believed he had already fought in a war prior to his resurrection and that he did not think he could fight another. Cyrell was also weary of the Traveler and its role in creating Ghosts, believing that no one should fight and die repeatedly in the name of a being with unknown motives. Despite these feelings, he could not bring himself to harm Strain or end his own life, believing such an action would be cowardly.
After hearing rumors of the Awoken in the Reef, Cyrell became convinced that they could hold the answers to the questions he had, and one question in particular that he refused to share with Strain. Upon their arrival in the Reef, Cyrell was pleased with their distance from the Traveler's Light and bid Strain farewell, revealing that while he searched for the Awoken who could answer his questions, he would also seek to prevent anyone else from going through the traumas he had suffered by killing Ghosts who had yet to find and revive their Guardians. Years later, Cyrell would become known as "the Ghost Hunter" and was seen by Strain once more in the Reef, having forged a new set of terrifying armor and dragging a chain of murdered Ghosts behind him, still seeking an answer from the Awoken.
Cyrell did not limit his hunt of Ghosts to the Reef. He menaced the Hunter and Ghost protector Micah-10 on Earth as she escorted her charges in their search for their Guardians. While pursuing her, Cyrell lost track of his prey in the Australis.