Travel to the Path of Conquest in Shadowmoon Valley. Once you have done a preliminary assessment of the area, use the Kor'kron Flare Gun to signal a Kor'kron Wind Rider. Speak with Overlord Or'barokh should you lose your Kor'kron Flare Gun and require a replacement.
Word has come from my wind riders, [player]. The Eclipsion blood elves are planning something big. They have begun forming their armies at the Path of Conquest, far to the southeast - adjacent to Eclipse Point.
I want you to travel to the Path of Conquest and assess the situation. Once you have done so, use this flare gun to signal a wind rider. One will swoop down from the sky to meet you. Inform them of what you have discovered and they will give you your next set of orders.