This quest is not available in game.
Speak with Archmage Khadgar to fly down to Azsuna.
<name>, we must find a way to reseal the Tomb of Sargeras. When I was in the Chamber of the Guardian below, I unearthed a tome that spoke of an ancient relic that might be the key to stopping the Legion. Our search begins here on the ancient elven island of Azsuna. Long ago, it was where the elves of Suramar perfected their mightiest of magics. Now it is a cursed ruins. I know that the demon hunters of the Illidari have established a camp on the island. Ready to take wing?