Have you met with the fortune-tellers of Zahar'ak in battle, honored ally? Each of these mystics carries a ritual tool known as a wildfire idol.
It is an iron statuette forged in the sacred flames of Ifrit, and possessed of a potent aura that invigorates any of the faithful that draw near. Though we have seized several of these idols before, their god-tempered nature rendered them irritatingly difficult to destroy.
But if we are to deny our hated enemy every advantage, then destroy them we must! I have thought long on this matter, and the mindless, raging nature of Ifrit's blessings might be made to work in our favor.
Our demented kin also draw strength from the fires of the Inferno altar. Casting wildfire idols into its flames will cause the blessings to feed one upon the other, igniting a conflagration violent enough to ensure their mutual destruction.
Is your task clear, honored ally? Hunt down the Zahar'ak fortune-tellers and relieve them of their ritual tools.
Bear the idols to the Inferno altar, and hurl them into the flames!
...Be sure to stand back from the explosion, honored ally. I would not have you perish in such a foolish manner.