Captive Proves His Worth

The man we took hostage is proving to be more profitable in our brig than it ever would be to ransom him. His knowledge of magic and runestones is plentiful. If we, with enough supervision, give him the materials to attune new runestones to something valuable, say a kind of drink, then the runestones can guide us towards it. We've seen how it works for gold and silver, just look at our stores! This wizard has more than proved his worth to us, and the only thing we have to worry about is him escaping.