Baron Sablemane has told you to bring him 7 Crust Burster Venom Glands. Return to him at the Circle of Blood in the Blade's Edge Mountains once you have procured them.
Very well, I'll create this trap, but first I want something in return.
There happens to be a nearby gronn that is in possession of an item that I want, but you can't face him, not yet anyway.
So, you and I are going to fashion a sleeping powder from the poison of the nearby crust bursters.
You'll find them in the Churning Gulch to the southwest. Bring me a number of their glands, and be quick about it!