The Battle of Duros, codenamed Operation: CERTAIN VALOR by the Imperial Special Operations Command and colloquially known as the Invasion of Borosk, was an engagement between the Galactic Empire and the Galactic Alliance Core Fleet on the Galactic Alliance-held world of Duros in the Core Worlds, in 130 ABY. It was one of the last battles of the waning Sith-Imperial War. The battle polarized many neutral worlds, who were horrified that the Sith were capable of ordering such atrocities.