Loot the Orders of the Prophet from an Erillion soldier
ok cool, I'll just get another w/e. Took me a couple kills but finally got another, seems about a 1 in 4ish drop rate for Orders of the Prophet. I only ever say a trooper drop them, but if you have the mercenary tasks you need to kill every type anyway.
If you pay attention to what Pika says, he tells you you need to kill a mature huntsman, a baby won't do. I got the drop off of a deadly huntsman because i didn't see any "mature" one around. So kill them til you get the drop of Poison of the Huntsman