The Eternal is a modified version of the Mercury class. She is fitted with additional heavy turrets on her dorsal and ventral sides. Her flightpods are more compact and completely overlap each other. She was assigned as the flagship of the 1st Colonial Expeditionary Group under the command of Brigadier General John Connors shortly after the Prometheus discovered a habitable plant not far beyond the redline. She later became the flagship of the Copernicus Colony once it was established.