From Halopedia, the Halo wiki
Over a century after the activation of the Halo Array, Voices accompanied the IsoDidact to Maethrillian with a group of other Forerunners. After they arrived at the ecumene's former capital, he volunteered to go with the IsoDidact, Chant-to-Green, and others to find the Organon. Along the way they encountered Crawler-like creatures. After encountering the Precursor construct known as Abaddon, Voices was among those who got away, along with the IsoDidact, Chant, Growth-Through-Trial-of-Change, and Finder-of-Things-Hidden. Voices informed the IsoDidact and Chant that Glory-of-a-Far-Dawn and Keeper-of-Stone-Songs would stay behind with Splendid-Dust-of-Ancient-Suns, with Dust saying he would buy them time. Soon the group encountered Abaddon again. After being threatened, Voices raised his rifle towards Abaddon and was turned into indigo dust.
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