Blast the Infernals!
Use the Fel Bomb while standing on the green glyph in Legion Hold, then report to Wing Commander Nuainn at Wildhammer Stronghold.
The device we've assembled won't win any beauty contests, but it should be capable of destroying the infernals amassed at Legion Hold. Judging from what the fel reaver power core's energy did to the Fetid Pool, it holds a respectable amount of explosive power.
If you set the device off in the middle of the green glyph at the hold, it should be in range to hit all of the infernals.
Required Level
67
Side
Alliance
Recommended Level
69
Difficulty
73
76
Start
End
Locations
Progress
Have you found a way to destroy the Legion's infernal stockpile?
Completion
Well done, Adventurer! I wish I could say that the Legion would give up after a setback like this, but you and I know better than that. The Deathforge that you learned about during your reconnaissance mission will be our next target.
Rewards
You will be able to choose one of these rewards:
You will also receive: 4 
10 
11 48
Gains
Upon completion of this quest you will gain:
- 12300 experience