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At some point, Trestin had participated in Emperor Calus' Menagerie, and following the Nightmares awakening on the moon she had started to become convinced by the Cabal Emperors ravings about an ineviatble end.
Later, she would participate in the Trials of Osiris together with her fireteam, Yara Croy and Sadhij Khuruf. In one round they faced a fireteam consisitng of Crimiq-5, Katake and Sola Scath. Sadhij overextended to kill Katake and died to Crimiq-5's retaliation, but this left Sola isolated. Trestin and Yara chose to engage her at this opportunity, but were overwhelmed by the Warlock. Trestin died painfully when Sola forced a Vortex Grenade into her armor, which also left Yara alone to be tortured by her opponent.
After the Black Fleet made contact on Europa, Trestin became one of the Guardians seeking to acquire the power of Stasis. Perhaps moved by Sola Scaths own actions, Trestin took extreme measures to reach her goal, culminating in the torture of Eliksni civilians deserting from House Salvation. When her fireteam sought to interfere they became her victims as well.
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