In a forgotten corner of the world, where the lines between past and present blur, Sonic and his friends encounter allies and enemies that time seemed to have left behind. New friendships are forged and old rivalries resurface as they face a threat that endangers the very existence of their universe. The Rainbow Emerald is a legendary gem that contains immense power. The user, its protector, must prevent it from falling into the wrong hands while traveling alongside Sonic and his friends through iconic locations from the Sonic universe.