Elzio Shilon, like many heroes, has grown up knowing only one purpose: Championing his nexus and homeland in Arena Battles. But when he uncovers a plot to sacrifice his kingdom's nexus to a power-hungry rival, he must reconsider everything he knew about the nexi, their rule, and their ultimate goal for universal dominion. Instead of fighting for his people, he teams up with an Echo Nexus, a being whose sole purpose is to be farmed by a larger nexus. Together, the two of them embark on a quest to defeat the nexi, not for power or glory, but for the salvation of mortal-kind.