When you open the package, a new task will pop up on the right side of the screen with instructions. You must go to the Cave of Time and talk to Chromie within the stipulated time to open three epic teamraids: The Burning Crusade, the Wrath of the Lich King, and Cataclysm. As long as you successfully defeat the 9 bosses in these three raids, you can unlock the special achievement "Memories of Fel, Frost and Fire" and the Obsidian Worldbreaker will be sent directly to your email as a reward.
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