The Battle of the Rainbow Star Cluster was an ambush of the Earth battleship Yamato by forces of the Great Garmillas Empire late in the Garmillas-Earth War. Occurring nearly a month after a crushing defeat at Balun, the battle became one of the empire's last chances to prevent Yamato from completing its journey to the planet Iscandar. It also became an opportunity for the legendary Garmillas general Erich Domel to restore his own and his family's damaged reputations, and for the empire's ruler, Abelt Dessler, to make a decisive political maneuver against Iscandar.