Curiosity Killed the Cat

A dark multi-step one, and missable throughout. You have to take the madman's broken sword to a blacksmith, repair it, return it to him and pass a hard speech check - after which he hangs himself (the trophy fires when you find him some hours later). Fumble the repair, skip returning it, or fail the check and it's gone. Save before the speech check, and go in with your Speech up.