Final Update:
You receive this quest from Mama Diggs in Dalaran once you have reached Rank 2 in all other Legion mining skills (leystone seam, living felslate, etc.). Go see her once you have everything else at Rank 2.
Thankfully, the below is now out of date, but will be kept on for posterity.
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Just my two cents, but the RNG on obtaining this is unacceptable. I turned 110 a few days after Legion launched, started doing WQs the next day, and have done the Infernal Brimstone WQ virtually every time it popped. No Rank 2 in sight.
I thought this could simply be a matter of me needing to be 800 mining (getting those last few points is quite tedious).
But then I hit 110 with my herbalist and received the Rank 2 felwort equivalent on the first day, on only the second felwort I ever herbed. Not 800 herbalism, either.
RNG is random, I know. But in my mind this highlights the problem with making quest items purely a matter of low drop rate RNG.
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Update 1: More than SIX MONTHS since first infernal kill. Still nothing. I don't know any miners that have R2 (as of 16 March 2017).
I would be storming Blizzard with torches and pitchforks if my soul hadn't shriveled and died long ago from this.
Update 2: It seems someone at Blizzard has taken notice. Patch notes for 7.2 state: "It should now be significantly easier to start the quest to learn 2-star and 3-star Infernal Brimstone mining."
We shall see, I guess. Now if only we could get compensated for the hundreds of lost opportunities for bloods and extra brimstone from their own screw up. Not going to hold my breath, though.
TheWoWDB
Spell: Mining Technique: Infernal BrimstoneFurthers your understanding of how to mine infernal brimstone more efficiently.
