in order to acquire this mount you must unlock the arr extremes trials. ifrit garuda titan leviathan ramuh shiva. each fight has the chance to drop the whistle to acquire their respective mount. once u have em all talk to the wandering minstral in mor dhona where u enter the raising stones. accept the quest and follow it to the location and use the item at the destination. after a cutscene u get your kirin mount enjoy.
https://store.playstation.com/#!/tid=CUSA00572_00
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