Rescue Treedin Merrythorn He can be found in the mill in Enchanted Lands ( -3, 3, -623 ) /waypoint -3, 3, -623 in a house. You have to kill his guards to progress the quest.
Search for "clues" in the The House of Circles ( -826, -6, -111 ) /waypoint -826, -6, -111 (east side of Rivervale) Warning: when you enter, 4 Vale Destroyers (Level 35) spawn and attack.
You have to examine three stacks of books. (use mouse-over on everything in that room, which is all books) After the third "clue" a book NPC will spawn. Hail it and progress through the conversation.
Return to Treedin Merrythorn in Rivervale.
Now you have to kill 3 named Nightbloods in the House of Circles ( -826, -6, -111 ) /waypoint -826, -6, -111 or northerly ( -812, 13, -339 ) /waypoint -812, 13, -339 area: