Bring 1 Large Brilliant Shard and 3 Abyssal Crests to Aurel Goldleaf in Cenarion Hold.
We think it is possible to use a wind stone to ambush a duke of the Abyssal Council. To do this, however, one must commune through the wind stone, and convince the council you are a middle ranked leader of the Twilight's Hammer.
Such a gambit requires a replica of the cult's medallion of station. I can create the medallion, but I will need a large brilliant shard, and crests worn by the Abyssal Templar.
Bring these to me and I will do the rest.