The Kingdom of Knights, Grandshelt.
Its people lived peaceful lives, blessed by the power of crystals.

Rain, commander of the airship squadron, receives a royal decree—investigate the Earth Shrine, where the magical barrier protecting it has waned, and determine the cause together with Lasswell, his childhood friend and deputy commander.
Upon reaching the innermost chamber of the shrine, the two encounter a mysterious man clad in black armor. Overwhelmed by his immense power, Rain and Lasswell are defeated, and the Earth Crystal is shattered before their eyes.
Though Rain and Lasswell narrowly survive, their airship is wrecked, and their comrades have fallen…

When Rain and Lasswell return, they find Grandshelt under attack by the armored man—Veritas of the Dark. They manage to rescue the king, but once again suffer a crushing defeat.

To protect the remaining Crystals scattered across the world, Rain and Lasswell set out on a journey in pursuit of Veritas of the Dark, joined by Fina, the mysterious girl they met in Grandshelt.

At this moment, none of them could have imagined the turbulent fate that awaited them.

And so, their quest began…