Go to North Qeynos through the sewer and enter the instance behind the Call to Arms smithy.
Hop on the sewer grate and then over the wall into the moat. Swim to the far north side of the moat past the barge.
Get out at the stairs and head to north end of the moat to hop over the wall again. Short walk to back of the smithy.
This zone is laid out the exact same as a Qeynos tradeskill instance. You need to find 3 things which can be found in different spots each time you do the quest (how much variation is unknown):
the recipe which is a flittering paper sitting on a bench (reported near workbenches and engraving tables)
used temper (to contaminate mixture) is on one of the shelves that hold the blue bottles (reported near forges)
alchemical temper (reported near chemistry tables)
There is a named mob in here who can see invis, Scribe Bogfizzle. She was one level higher solo and gave -100 Ironforge Exchange faction when killed. Also note that each of the doors is guarded by heroic guards.
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