The Vision Guide guides your soul to the resting place of the final Thunderlord artifact.
Use the Fiery Soul Fragment to transform your spirit into a vision guide. Speak with Rokgah Bloodgrip at Thunderlord Stronghold after your vision has guided you to the location of the final Thunderlord relic.
You will need:
<race> fool. You almost destroyed the drum!
I've worked too hard to get here, and my hands have been empty up until now. At least you were able to succeed where the others only met with failure, or worse.
It is time to evoke a vision that will lead you to the last relic that I have been seeking.
Take this fiery fragment of my soul. Use it to transform your body into flame and denature your spirit into a vision guide that will shoot forth to reveal the location of the final Thunderlord relic.
Just use the Fragment that is given to you. You'll turn into a wisp-like being and will follow a path from Thunderlord Stronghold, past Bladespire Hold, and finally go to the back of the Draenethyst Mine.
What did you see? Tell me, I must know where it is!
The back of the Draenethyst Mine? The Bloodmaul clan must have stolen it from the Bladespire ogres.
Bah! That is too far away... too deep into Bloodmaul territory for me to travel.
But you. You know the path. You will go there in my stead!