After the first battle, the Covenant Empire left the colony alone, focusing their attention on other worlds with significant Human populations. The United Nations Space Command abandoned Arcadia, leaving its population centers abandoned to nature. A small rural community later started in Abaskun, a fertile area on the continent of Mu, and though self-governed and mostly lawless, it provided the Humans with food, water, and other vital resources.
Returning to finish what they started almost eighteen years earlier, Arcadia was once again attacked by the Covenant, though without any permanent UNSC Naval or land forces present, the attack succeeded and Arcadia was ultimately glassed.
Dr. Catherine Halsey watched the destruction of Arcadia from cameras mounted on a meteorological satellite. She noticed that the Covenant attacked the planet with much more ferocity than was their norm, possibly because they had been defeated during their first attack on the planet. The satellite was destroyed before the glassing operation was completed. Halsey was greatly distraught by the sight of Arcadia's destruction.