West of Un'Goro Crater, via the northwestern ridge, is a harsh wasteland - Silithus.  Few know that an ancient war was waged there between the night elves and a malign, alien power.  The evil was sealed, but now we suspect that forces work to stir this... unspeakable horror.$B$BSeek out Layo Starstrike, one of our agents in Silithus; look for him at Valor's Rest, the final resting spot for the fallen of the wastes.  Give him this letter, and he will give you his trust accordingly.