Gather 8 Windfury Cones north of Thunder Bluff, use them with the Mortar and Pestle, then return to Boarton Shadetotem in Thunder Bluff with the result.
Maybe your skills lie with poisons, not disguises. The Harpies to the north nest in a tree which produces a resin of potent toxicity. Gather the fallen cones around the nests, then crush them into a salve. When applied to a blade this salve will sear your opponent's wounds into their flesh and turn their blood to salt.
