From Halopedia, the Halo wiki
During the evacuation of Erde-Tyrene in the final years of the Forerunner-Flood war, Carrier was the chief Lifeworker on the planet. He, along with two other Lifeworkers and Catalog, oversaw the mass evacuation of an African plain. During the evacuation, he received a signal from his ship informing him that the Librarian was in the system, and he was given orders to take Catalog to her ship. Another Lifeworker, Celebrator-of-Birth, asked if they were going to meet her. Carrier said they would not, as the human community of Marontik had not yet been processed. Carrier then escorted Catalog to the Lifeshaper's ship aboard the Lifeworkers' seeker transport. Catalog remained silent during the journey, as it saw no benefit in discussing matters with the Lifeworker due to his limited power and culpability. Immediately upon arrival aboard the Librarian's vessel, Carrier left Catalog and returned to Erde-Tyrene.
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