Estinien asks you to procure wooly yak hides to produce a signal fire of purple flame that you will use to lure the heretics.
Requirements
This quest is available if you have completed the quest Camp of the Convictors.
Starting the Quest
Talk to Estinien in the Coerthas Western Highlands to begin the quest.
Obtain Yak Hides
Go north to where the orange arrow is pointing in the minimap. The locations of Wooly Yaks are marked in the minimap. Kill Wooly Yaks until you have obtained two yak hides.
Deliver the Yak Hides
Go south up the slope, then go northwest. Estinien is standing on a hill. Go to the northwest side of the hill to find a slope up to the top. Talk to Estinien to hand over the Yak Hides and complete 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.
Unlock Flying in the Coerthas Western Highlands
"Purple Flame, Purple Flame" is the final quest for unlocking Coerthas Western Highlands Aether Currents. If you have completed the other Aether Current quests and attuned to the Aether Currents in the field, which you can find using the Aether Compass in Main Menu > Duty > Collection, you will be able to fly in Coerthas Western Highlands.
Next Main Scenario Quest
After you complete the quest, you will need to be at least level 52 to proceed to the next quest. After you reach level 52, talk to Ysayle to accept the next quest: Where the Chocobos Roam.
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