... like many of the puzzles in this game, an item (that is otherwise outside of any quest) you find in one spot is used close by for something else. In this case, the the pickled Trynnie is found in the castle, on the same floor as Ferro. Once you know the answer it is obvious.Another one like this is the fairy dust + rotten meat combination .. both found in nearly the same spot, but (to me) it was far from obvious that the two should be combined (until someone told me, then it was one of those *smacks self in forehead* moments).
Tools for Wizardry(r) 7