Ginga Eiyuu Densetsu: Die Neue These - Sakubou

After Yang Wen-li successfully captures the Iserlohn Fortress, the Free Planets Alliance grows bolder in its militaristic ambitions. With recent incursions into Galactic Empire territory and the possession of a perfect beachhead, the Alliance is now able to deal significant damage to the Empire. However, Reinhard von Lohengramm has no intention of allowing the Free Planets Alliance to gain a foothold. He is adamant about carrying on his best friend Siegfried Kircheis' dearest wish: to be the one to unite the universe.

As wide-scale military clashes continue, the opportunist Adrian Rubinsky, Fezzan's ambitious leader, attempts to take advantage of the war to further his personal goals.

(Source: MAL Rewrite)

Note: It received a limited special screening in theaters with the episodes spliced together into 3 separate movies.