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He created the Lord of Wolves, a modified Fallen Shrapnel Launcher, for use by the Crows, and later Guardians. He found happiness in refining enemy technology and in exploring new ways in which a weapon could be used.
Jolyon was famous among the Crows, and had been companions with Uldren for a long time. Any time Uldren went out on a big mission, Jolyon was by his side.
Their last exploit together was the first known human expedition into the Black Garden. To enter its Gate, which only opened for Vex, they infiltrated Cabal territory and provoked them into launching a major assault on it, forcing the Gate to summon a Gate Lord to defend it. While the Gate Lord was distracted by the impending Cabal attack, Jolyon and Uldren slipped past it and into the Black Garden.
What Uldren found fascinating in the Black Garden, Jolyon was wary of and disturbed by. When they departed it, Jolyon continued to keep to himself despite their feat, telling Uldren that he didn't want anyone to know what he saw in there and wished he didn't remember. Mara Sov confronted Jolyon upon their return, accusing him of treason and questioning his loyalty to her. He explained it was not a matter of disloyalty to her but loyalty to Uldren, the same loyalty her brother held for her. Afterwards, he suffered recurring dreams about the Black Garden.
Much later, after the Red War, a delusional and fugitive Uldren Sov turned himself in to the Reef. Jolyon was one of the members of the strike team who took Uldren in before his imprisonment in the Prison of Elders. Though Jolyon caught Uldren's eyes, the prince failed to recognize him.
After Uldren's death, Petra visited Jolyon in the field, asking if he wanted to pay his last respects to the body. Though Jolyon grieved him, he rejected her offer, saying "He's dead. He died a long time before you shot him. Or if you didn't, you helped that Guardian do it." 
Personality and Traits
Jolyon is tall and handsome, with narrow, intelligent eyes. He is calm, careful, and practically minded: he keeps his thoughts to himself, prefers to stay away from what he doesn't understand, and doesn't like taking unnecessary risks. He doesn't like hearing or keeping secrets.
Jolyon and Uldren were extremely close. Jolyon was comfortable talking back to Uldren, and Uldren became much more animated and flippant when he was around Jolyon, who he called Jol. After Uldren became corrupted and betrayed his people, Jolyon was heavily conflicted over his feelings regarding his former friend but accepted that the Uldren he once knew is gone. Still, he expressed some bitterness towards Petra for her role in Uldren's death, brushing off her condolences.
His preferred weapon is the gigantic Supremacy sniper rifle.
List of appearances