Bring a Shadowstalker Scalp to Maurin Bonesplitter in Desolace.
I believe I can find this demon lord given the proper reagents.
If he is indeed as powerful as I suspect, I will need items gathered from deadly creatures. But you act in the Warchief's name, so I am sure you will accept my task.
First, I will have to break any wards he has against scrying. For this, I will need the scalp from a satyr--but not any satyr. The scalp must come from a Hatefury shadowstalker.
Search for them among the ancient ruins in the northeast of Desolace.