In the world of Granide, people live happy lives thanks to the mana produced by the World Tree. However, legend has it that when the world is in danger, the World Tree will produce a hero known as a "Descender." One day, Kannono Earhart of the Ad Libitum guild sees the game's protagonist fall from the sky. The fallen protagonist has lost their memories from the impact, so Kannono invites them to join Ad Libitum and travel the world on the enormous Van Eltia ship that serves as its mobile base. As the World Tree has become saturated with negative thoughts, mana-consuming life forms are now being created, and the Descender must stand against them to save the world.
—Tales Channel PLUS