Blue Star humans were swallowed up by the "Canopy of the Undead" and collectively fell into the "Skeleton Islands" - a sea area shrouded in eternal night. Billions of independent islands are composed of dead bones, rotten soil and netherworld swamps. The air is filled with the "death energy" that nourishes the undead, and is occasionally embellished with thin "spiritual energy" (soul energy). The two are like water and fire, and will be annihilated when they come into contact.
Each time traveler is forced to bind at the beginning:
