The control stone first appears in the story when the mortally-wounded Rastel (Lastelle) gives it to Nausicaä after the crash of the Pejitei Brig  with the request to give it to her elder brother and the admonishment that the Vai Emperor should never get it.
Nausicaä takes the stone and returns to the Valley of the Wind with it . Kushana finds the crashed Pejitei Brig with a troop of Worm Handlers and tracks the stone to the Valley . After a confrontation with Nausicaä, she is convinced that the stone is being held by Nausicaä and uses the Periphery Campaign to try to get it.
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