The primary narrative focuses around Ace Flynn—a feisty messenger working for the black market. He lives with his telepathic sister, Lynx, as their single mother was killed a years ago while working as a bioengineer. They live in the dystopian Understory level of the scaling metropolis, Constellation City, which is ruled over by the totalitarian Union. He prefers to keep his head down and not get involved in the problems of others, as his paternal duties provide enough responsibilities.
However, this all changes when Ace meets the dashing young Dallas, a member of the freedom fighting organization: PHNX. Though a series of unplanned events, Ace becomes associated with Dallas and his fellow rebels, Tuesday and Port. This marks him a public enemy and soon the Union goes after both Ace and his sister. Although Dallas is there to fight back Union officials, Lynx is kidnapped as Ace and his new love interest make their escape. Determined to rescue his sister, Ace joins up with PHNX to infiltrate the Union in hopes of taking down their main servers and save Lynx.
Although the Union is the primary antagonist, Ace and his new allies also must deal with the dreaded Fiends—terrifying creatures that have recently resurfaced in Constellation. The heroes must uncover these creatures’ dark secrets and learn their part in the undoing of the Union.
Additionally, members of PHNX all have the ability to wield unique magic types and weapons that resonate from their connection to Neo Earth’s mystical Halo. It soon becomes clear that not only does Lynx possess magnificent, untapped power of the caliber, but so does her brother. Ace must work to unlock and master his own power in order to save his sister before the Union takes notice and extorts her power for their own evil purposes.