The Grand Exile is a massive Exile that was constructed by the people of Ades and the Guild of Earth, who resented being left behind during the Earth Regeneration Plan and wished to join the other refugees in space; however, it was never completed, for unknown reasons. The gene for its Key was passed down through the line of the Augustas of Ades; its known Keys are Farahnāz Augusta and Sārā Augusta, though only Sārā was ever used to activate it.
The Grand Exile is featured on the Augusta's flag, and the wing of a Grand Exile is seen at the Ruins of White. Oddly, it was partially built in Glacies, which could be for various reasons. There may have been multiple Grand Exiles, or there was better access to raw materials even though Glacians seem to have little due to the lack of massive battle ships.
It apparently was being flown backwards the entire time in order to repurpose the thrusters as cannons. The thrusters are unique because they do not seem to use loops or rings of tubing to circulate Claudia-water mixures, and the parts and jets are not the orange color some expects from combustible Claudia-alcohol mixtures.