Tempering The Blade (Alliance)

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2. Run Forge of Souls Normal or Heroic
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4. Kill final boss and use the item at the crucible or as @saberoy said "the fancy fireplace".
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6. Important Note: The turn in to this quest is outside of the instance in one of the halls leading to the instance stone. This will give you the follow up to just turn around and run Halls of Reflection (No, not Soloable that I can see)
7. 
   

Quite simple, do the instance like normal, then after you kill the last boss, use the item at the fancy fireplace behind him.

Rogues can complete this quest by themselves on normal. I stealthed all the way to the boss, garroted then vanished, and used the item on the now active crucible.