Collect $1oa Unwaning Bones.
When I was sailing in, I noticed the remains of an unbelievably large beast on the nearby peninsula. Whatever it was, it must have been strong, making it the perfect source for the bone elements of the drums. Go to the peninsula, 'Xibala' I've heard it called, and fill a bag with the bones you find. If you come across any of those damned Alliance, show them no mercy. They did this to themselves.