Prequel to the original series, focusing on Reinhard and his steps up the chain of command in the Galactic Empire. A collection of independent short stories taking place prior to the Overture to a New War, some of which are adapted from the novel and some of which are completely original.
Watch Legend of the Galactic Heroes Gaiden: A Hundred Billion Stars episode 1 online — subbed and dubbed, with automatic AniList / MyAnimeList progress sync.