Looking over the captured attack plans, you find a map of the Eastern Kingdoms and Kalimdor with major settlements marked. Reading over the orders, you learn that Kvaldir captains have drafted plans for a series of devastating raids.
According to the orders, the attacks are to begin after Mistcaller Yngvar "consults the Heart of the Mists." Perhaps you could delay the attacks by capturing the omen from the Mistcaller's Cave on the western side of Hrothgar's Landing and notify Justicar Mariel Trueheart.
What is it you've found <name>?
<Mariel accepts the orders and the captured seeing crystal and examines both.>
Good work, <name>, and quick thinking. I'm sure the theft of this trinket wont slow them down for long, but I think you've bought us time to warn the leaders of the Horde and Alliance about the impending attacks.
Patch 3.2.2 (2009-09-22): Added.