It is pretty disgusting, but nothing I couldn't live without. If I can stand around wanding a boss, I'm already regenning well over 100 mana/tick just standing around, and with a stormrager JoW is "only" the equivalent of 50 or so more mana per tick.

It is basically essential for shadow dps, though. I dabbled in pve dps briefly, and I found that with every consumable I could use, I could sustain 300-400 dps for about three minutes (and spend 100g a fight, as major manas were expensive then). With JoW, I pulled off 320 dps on a 10 minute ebonroc fight. It effectivly cuts the cost of mind flay by almost a third, which is enough that consumables come close to breaking even with mana usage.

I've often been curious...anyone have that coefficient for mind flay? Can't say I've ever seen a number from anyone that inspired great confidence.

The one set of data I really witnessed for myself was from a video of a shadowpriest on rag, but his mindflay was ticking for something absurd like the 400 range. B/c of debuffs it fluxuated quite a lot though and I'm not positive what all gear he had (he def. had flask + shadowpower, so that would explain some).

I know AM is really shitty for +dmg on mages (20.6% for the optimal +dmg -> dps conversion) since it's a 5 second channel. Where mind flay was a 3 second channel though (so I'd guess from that that it gets ~28.6% per tic base) and with darkness, weaving, and shadowform, I'd always assumed a shadowpriest's mindflay had one of the best base conversions of +dmg -> dps prior to accounting for crit or base resist rates. With the 28.6 it would be close to 40% with those debuffs vs. an optimal conversion frostmage at 35.5% or an optimal conversion warlock at 42.9% with succy sac/rez. A more standard warlock with the imp out would be 37.7%.

It's 0.45.

It's not that bad given that +dmg/heal gear improves a shadow priest's secondary role somewhat as well and you get a +25% multiplier with talents instead of the usual caster 10%. Still, the rift becomes wider and wider.

Edit: To underline a point though, this is all a rather esoteric discussion that assumes you're min/maxing your way to the absolutely ideal raid makeup. Player competency and gear makes up for 90% of the loss incurred by speccing a certain way. My guild is pretty successful, being at princess huhu currently despite focusing on pvp, and it's not an uncommon thing at all for someone to basically say "to hell with it" and spec whatever. We have retnub pallies, ooc feral druids, bm hunters and even an oomkin. They still contribute to the raid, they still have fun, and at the end of the day as long as you are advancing at a steady rate in endgame pve the rest is just a game.

Yeah, we haven't really had people gettin' the shadow bug lately (we have one priest with shadowweaving...none with shadowform...right now anyhow they all seem to love PI, and that's fine), it's just been a matter of "do I want to invest a day of my life and level a priest past 20, just to see what the conversion is?". Cuz I NEED to know these things and most of my guild isn't interested enough to give me a decent body of data.

Thanks much :).

Edit #2: I started browsing my guild's priest forums on a whim and there are some very interesting numbers suggesting that shadow focus is an under-appreciated and rather massive overall raid dps boost akin to the whole glancing blows formulas that have been popping up recently for rogues/warriors. I've no idea how important this is since to my knowledge to no other caster has a similar talent and I play a melee hybrid. Thought I'd bring it up though.

Personally, I love the combo of having shadow priests and warlocks together. I don't think there is a school of spell that has more damage increasing target debuffs. The holy dps just can't compare to the debuff power of shadow when applied to an entire raid.

Curse of Shadows (10%), Improved Shadowbolt Proc (20%, and is up relatively frequently if all the locks in the raid have it), Shadow Weaving (15%) give about a 51% increase to all shadow damage to the target if the debuffs multiply, or 45% if they are just additive.

Having all these debuffs means a shadow priest can get away with having less +shadow and more dmg/heal, and still be a reliable source of dps without completely destroying their ability to heal.

Not to mention if you get the shadowform priest to leech a power infusion off your local disc priest, and suddenly he's dealing more than twice the shadow damage off the tooltip. That's some major scaling.

Granted it doesn't beat the warlock with his rez'd/DS'd succubus + power infusion, dealing 230% of his normal unbuffed shadowbolts. With 700ish (http://ctprofiles.net/22018 my nonAQ dream gear setup) +shadow damage, you're looking at shadow bolt hits of around 2500, or a mere 2100ish without power infusion.

It's one of the best talents in the game, I said that it was ridiculous in my expanded post.

The reasoning behind it being such a good spell is that it reduces the resistance of a mob based upon that mob's overall shadow resistance, so as the mobs get harder and harder, the amount of "good" the talent is goes up.

with maxed shadow focus and +4% to hit you'll never get a resist on any mob in the game right now that is not specifically resistant to shadow (black drakonids?).
It's because of the way that %hit and the %lowered resists work together.

To contribute a little bit to the discussion at hand, I'll recommend a good shadow build for raiding, and the explaination of why I chose specific talents.
My Shadow Build

Blackout over spirit tap because chances are you aren't going to kill something, and there's a few fights where the blackout could be handy ;)

imp swp: improves mana efficiency
shadow weaving: Warlock love
Vamp and imp vamp: 30% of your damage goes to the MT as healing, great talent combo.
darkness and SF: This is a big damage build.

Med & IF: Helps a bit with mana longevity
Mental Agility: The second best talent right behind Mind Flay, for a shadow priest.

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