A mysterious rift between dimensions merges the Mushroom Kingdom with Sonic’s world. Bowser and Dr. Eggman join forces, combining Koopa tech with Eggman’s robots to seize control of both worlds.
Bowser wants to claim Sonic’s Chaos Emeralds to become unstoppable.
Eggman wants to use Mario’s Power Stars to fuel a planet-sized robot.
The collision of worlds causes zones/kingdoms to merge into surreal hybrid levels.
Mario and Sonic reluctantly team up, along with Luigi, Tails, Peach, Knuckles, and others. The chaos tears through space-time, threatening to merge all Nintendo and SEGA worlds into one collapsing mess.
