Aer, Neviril, and (at her request) Yun are delegated to accompany Onasia and several other religious officials to the Ruins, aboard the Messis. At the Ruins, the sibyllae are told the secret of the Emerald Ri MÄjon: it allows the Simoun to travel in time. Chor Dextra was formed for that purpose, and used the Ruins as its training ground. In a last-ditch effort to save the rapidly failing Simulacran war effort, the chief priestess of the Grand Temple orders Aer and Neviril to reactivate Chor Dextra and perform the Emerald Ri MÄjon to prevent the war from occurring in the first place...