Just after you reach an impasse, you receive assistance from an unexpected source.
This quest is available if you have completed the quest Forever and Ever Apart.
Starting the Quest
Talk to Alisaie in Sui-no-Sato in the Ruby Sea to begin the quest. There will be a cutscene. This one is important, so it is recommended to watch it either now or via the Unending Journey in an inn room.
Speak with Alisaie
Go southwest and go into the whirlpool to exit Sui-no-Sato. Go southwest to where the orange arrow is pointing in the minimap. Talk to Alisaie to proceed.
Use the Enchanted Lamp
Go to the southwest edge of the orange circle on the map and use the Enchanted Lamp from the Key Items section of your inventory, or by using the icon to the right of the quest name in your list of active quests. If you used it in the correct location, a Shimmering Object will appear.
Obtain the Yasakani-no-Magatama
Go to the quest icon on the map and check on the Shimmering Object.
Show the Yasakani-no-Magatama to Alisaie
Go to the quest icon on the map and talk to Alisaie to hand over the Yasakani-no-Magatama and complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Alisaie to accept the next quest: The Whims of the Divine.