The story takes place in the Divine Era, after the start of the Common Era. The world has fallen to Vertex, emissaries sent by the gods to destroy humanity. The gods who stand with humanity have gathered together as the Divine Tree, raising a barrier to protect Shikoku and the last surviving humans.
In Divine Era 300, Vertex once again invades Shikoku. Six members of the Hero Club at Sanshu Middle School are unexpectedly chosen by the Divine Tree to become the new heroes. The third-generation heroes, led by Nogi Wakane and Yuuki Yuuna, embark on a new battle. Can they escape the fate of being heroes?
