коммент с вовхэда:

http://www.wowhead.com/item=51316
By Soji (872 – 5·9) on 2010/06/28 (Patch 3.3.5)
I completed this quest today:
I had the quest to kill the Lich King: The Lich King's Last Stand.
When we killed the Lich King on 25 man Normal i also got the quest item Sealed Chest...
Т.е. ребята лутали с нормы ага.