The Celestial Star is the main item from Return to Ztarragus's Island. This is the item that split Celestius into Starragus and Ztarragus. It was also used by Geminon to trap Starragus in a rock. In Return to Ztarragus's Island, It was split into 6 pieces and scattered all over the island. They were revealed after a bright flash of light came from the island. Rockolanius used it to break free and become Starragus again. Then he and Ztarragus used it to reunite and become Celestius again.
- The Celestial Star is similar to the Cobalt Star from Mario and Luigi: Partners in Time.