In YE 16, shocked by the assassination of their leader by Yamatai and humiliated over their defeat in Hell in the Second Elysian War, Elysia directly attacked the Yamatai Star Empire.

Yamatai responded by invading Heavens using General Ketsurui Yui's Armies of the Precious Sword. By YE 18, most Elysian territory was in such ruined condition that the populace made an exodus to Elysia Novus.