It begins with Examine the Vessel, followed by Thunderaan the Windseeker, culminating with Rise, Thunderfury!.
The quest chain begins when you loot one half of the Bindings, which drop off Baron Geddon and Garr in Molten Core. Upon looting either of these, you must then travel to Silithus and speak with Highlord Demitrian. He will give you the Vessel of Rebirth, which begins the quest line.
The next quest requires you to present the following items to Demitrian:
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Both the left and the right Bindings of the Windseeker.
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Essence of the Firelord, which is a 100% drop from Ragnaros if you have the quest.
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10x Elementium Bar, obtained from smelting rare Molten Core and Blackwing Lair reagents.
Bring a raid with you when you return with the required items to Demitrian, because he will promptly summon Thunderaan, whom is not the least bit happy that he was locked away for so long. Defeating Thunderaan causes him to drop his blade, whereupon you can receive the Dormant Wind Kissed Blade. Deliver this to the now rather cowed Highlord, and he will make Thunderfury, Blessed Blade of the Windseeker for you.