Jiiiii～

Riliu and Jowy, two young soldiers from the Highland Kingdom, come under attack at night while on an expedition in the mountains. While fleeing,　they jump into a waterfall and are swept away separately, each ending up in the territory of the States Army—their enemy. After reuniting, the two set out for their hometown.

The Highland Army, led by Luca Blight, begins its advance toward the Mercenary Fortress where Riliu and friends have taken refuge. Riliu and Jowy are determined to fight. After burning down Toto Village, Luca finally reaches the Mercenary Fortress, where a fierce battle ensues.

Riliu and friends escape the Mercenary Fortress and set out for Muse. Spending the night at a shrine, Riliu and Jowy encounter a mysterious light. They relive memories from the past and come to bear their respective True Runes on their right hand.

After reuniting in Muse, Riliu and friends witness the situation in the City-States, which are far from united. When Riliu and Jowy go undercover to investigate the Highland Army camp, their identities are exposed, and Highland soldiers give chase.

After being captured, Jowy learns that the Highland Army is planning a night attack on Muse. Determined to stop it, he makes Luca a proposal. Jowy returns safely to Muse. Riliu, Nanami, and Pilika are overjoyed to see him, but Jowy seems troubled. Riou can't help but wonder what's bothering him. As night falls, Riliu and Nanami visit Anabelle’s office at City Hall to hear about Genkaku. But when they open the door, they encounter a gruesome sight. At the same time, the Highland Army launches its surprise attack on Muse. Amid the chaos, Riliu and the others try to break through the enemy's ranks.