I was checking my achievements this morning and found out that I still haven’t completed the First Aid achievement Ultimate Triage.
The objective is to heal another player or yourself using a Heavy Frostweave Bandage when the health is less than 5%. As a warlock, I need not look for a player with an hp of less than 5%. I just Life Tap’d then Hellfire’d until I was less than 5% hp then bandaged up and Voila! I got the achievement.
Then I remember that I haven’t really used Hellfire for a while now. Back in The Burning Crusades, Hellfire has been my buddy when our raiding team is about to wipe in Black Temple. When I sense it coming, I just Life Tap and Hellfire to death and suffer no durability damage. I never and don’t plan to use it in raiding for obvious reasons unless Blizzard makes some changes to it that would make it part of the rotation or something.
I wasn’t sure earlier today if it’s still doable in Wrath. And I have proven that it still works. So I can still use my Hellfire during impending wipes and save my ass from humongous repair bills.
And here’s what WoWWiki has to say about Hellfire’s utility:
Hellfire is an optional finishing move for Affliction Warlocks when Drain Tanking. However, it should only be used against green-level creatures unless there is a healer around, for it will usually damage the caster more than the mobs are.
Warlocks are unable to resist the damage that Hellfire does to themselves unless they use the Sacrifice ability of the Voidwalker, then the shield will take the damage until the shield fails or the effect is interrupted by moving.
If the warlock dies from this spell’s effect, they take no durability damage. This allows the Warlock to save some repair costs when faced with certain doom. In such a scenario, a Warlock will typically use life tap to get low on health fast, then use Hellfire. This is commonly referred to as “Ghost Walking” and is a common way to get into Scholomance without possessing the Skeleton key.
So there ya go. Enjoy your Hellfire! 
