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In this event, the Nephalem needs to find out who slaughtered the noblemen and women. This is easily accomplished by going through two doors. In the last chamber, a party of three Murderous Thugs and their leader, Gorrel, a Superunique Human, are found. Talk to Gorrel who will quickly disagree with you. No way out then than killing Gorrel and his conspirators. Upon Gorrel's death, The King's Note to Lord Wynton Lore Book drops.
This event is associated with the "People Finder" Achievement. Noble Deaths is one of the events that must be completed to obtain the "Long Live the King" Achievement.