UNSC Promise of Dawn
The Promise was involved in the events surrounding the fall of Reach in an unknown capacity. It was the vessel chosen for the safekeeping of the nascent Smart AI Gabriela, the only known AI containing the entirety of Human history. The vessel was believed lost after the events at Reach, a belief which held for approximately a year before the Office of Naval Intelligence received a distress call from one of the survivors on Sephune III, as they had been trapped on the planet for a year while Dr. Chen Bax worked to free Gabriela's matrix from the ship without informing the majority of his surviving followers. The frigate had made a hard landing on the surface of the planet, and had become trapped in ice and snow, the vessel itself being protected externally mines, as well as at least two turrets located near the access panel for Gabriela's matrix.
The vessel was destroyed when Chen detonated its self-destruct via remote. This created an avalanche which took out a large portion of a Covenant force intent on killing the humans, saving the survivors by allowing them time to escape.
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