The Bugle Call: Song of War manga volume 2 features story by Mozuku Sora and art by Higoro Toumori.

The time has come for Luca's first real campaign. A fort on the border of the Holy Realm is under siege by the army of the Erin Empire, and it's up to Luca and his newfound compatriots to defend it. The powers of the Branch-hexed make them unstoppable versus regular troops, but the forces arrayed against them have their own Branch-hexed in service. Luca now faces a true test of his abilities against fierce opposition!