The Mysticons and Proxima go on an undersea quest to destroy Queen Necrafa's broken mask by hurling it right into the fiery core of the Rift of Ruin; a volcanic trench that is located in the deepest depths of the sea. Proxima is tasked with guarding the fragment with her very life. On the surface, Malvaron attempts to capture his sister Tazma, who has secluded herself within the Spectral Hand's lair, with help from Doug and Choko.
Four girls are summoned to become the legendary heroes known as the Mysticons. They will undertake a quest to find the Codex.