On 21 March 794 UC, Imperial forces under the overall command of Gregor von Mückenberger invade the Van-Fleet Starzone and engage with Alliance forces commanded by Lasalle Lobos. The battle progresses in an inconclusive fashion, frustrating Reinhard von Müsel, who had recently been promoted as Commodore and had received command of a squadron under the Grimmelshausen Fleet, greatly as he laments the incompetence of both forces and his own relative powerlessness.
Prequel to the original series, focusing on Reinhard and his steps up the chain of command in the Galactic Empire. Also focusing on the FPA's Yang Wen-li. A chronicle on how he earned the title "The Hero of El Facile" and his handling of assignments he received after the historic event. Spiral Labyrinth also continues with the background of Reinhard and Kircheis where the first Gaiden left off.
