It was my understanding that the debuff from FFB DID activate TtW, since it also has a damage compnent which bosses are not immune to, whereas the frostbolt debuff did not as bosses are 'fully immune' to the effects.

Just to make it 100% safe - that means the scaling is simply 3/3.5 = 85.7% now?

Also, has there been any testing on the cooldown on Brain Freeze? The easiest test would probably be to spam a low rank Frostbolt (fast cast time, to simulate a high-haste environment) and check the combat log for the fastest reprocs.

Correct on the coefficient.

I have not tested Brain Freeze beyond trying it out to see the pretty colors. However, a report on the PTR forum indicates that the ICD may not yet be implemented; a guy was able to get repeated procs (three in a row) from FFB: Frostbolt -> Proc -> FFB -> Proc -> FFB -> Proc -> FFB.

Early days I know, but is there any preliminary math on the +5% Frostbolt Spellpower scaling combined with the FFB change to Brain Freeze in 3.3.3 in terms of how it rates to Fire/Arcane?

Edited for Spelling:

With the 3.3.3 changes (should they go live) the difference between frost and arcane is significantly reduced. Lhivera's run some simulations estimating an ~10% less than arcane on a stand and pew fight. In my experience in ICC frost was about 15-25% less dps than arcane.
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I've only seen frost on par with (but not beating) arcane on one encounter and that was due to the mechanics of the fight more than anything. Sindragosa's unchained magic puts a serious dampener on arcane dps, for which frost's elemental can compensate (depending on the uptime of the debuff; it's only a serious problem if it's 10 man and you lack casters to soak the UM debuff for you).

The biggest problem there, however, is the relative lack of dps on adds, ie the ice blocks. Deep freeze does no damage to the blocks and therefore your dps is insufficient compared to arcane for breaking the blocks.

I don't agree with you on Sindragosa - Ice block means that you can (carefully) stack unchained magic ad infinitum once every four minutes; however, I'm convinced that frost with improved blizzard is hands down superior from a dps, mana management, and utility standpoint on the Valithria encounter. If you spec into frost warding, you can have pretty much unlimited mana that fight, not to mention the fact that you can snare just about every add that spawns.

I find that a Frostfire PvP build works great on Dreamweaver. I say PvP build because a normal Frostfire build typically won't have Firestarter and Molten Shields (which I'll get to later). The instant, mana free Flamestrike every 20 & 30 seconds really adds up. It allows very quick AoE burst on suppressors and Rot Worms, and gives both melee and ranged AoE. I also have 1/3 Impact, and most of the mobs in the encounter can be stunned (Fire Blast with Impact proc), snared/knocked back (to interrupt spell casting with Blast Wave), and disoriented (dragon's breath). This is all incredibly useful against suppressors (they can be dazed, but not disoriented; they can be knocked back, but it won't interrupt their channeling).

I'm also specced 2/2 Molten Shields, so while I don't get mana back, I do have a 35% (glyphed) chance to reflect frost/fire. And I have Imp Fire Blast -- against Blazing Skeletons, I can barely get in a Frostfire Bolt before it dies -- Scorch and Fire Blast seem to be much more efficient.

I haven't had any mana problems on the fight thanks to the ridiculously low cost of Dragon's Breath and Blast Wave (which Blizzard toned down from near 30% to 7%), and the free Flamestrikes, and I can easily put out more damage than anyone else. I keep living bomb up on targets that take longer to kill (Abominations and Archmages), so it's not cast as often (Skeletons and Suppressors die too fast for LB).

As far as I know TigaFin, Nibelung was changed in how it procs. It now procs on spell cast, not on damage (or not on damage alone). It may have always been like this, as I had Nibelung proc off the Rocket Pack's 'blast wave' type spell on Gunship (before the encounter had begun -- no damage had occured). I've also had Nibelung proc lately from just casting Living Bomb. The DoT ticks won't proc it, but the application of LB on a target will.

One thing that does proc Nibelung though is Molten Armor. Whenever you take melee damage, Molten Armor reflects back a spell cast, which has a chance to proc Nibelung. If you're specced 2 points into Molten Shields (which I am in my Frostfire PvP build, which I use for Dreamwalker*, as mentioned), then whenever you take ranged damage (physical or magic), Molten Armor will again hit back. All of these are occurrences are considered spells, which is why I see many more Nibelung procs in PvP than I do in PvE.

I've almost thought of speccing 2 points into Molten Shields in my Fireball build for this reason -- by taking 2 points out of Flame Throwing. It would dramatically increase the number of Nibelung procs on any fight with ranged damage. Although, it would need to have a caster to reflect back, so I'm not certain that AoE pulses would trigger Molten Armor. But think of Frostbolt Volleys as an example.

Since I'm not Frost though, I can't control my Val'kyrs. I have been wondering though whether or not Frost gets additional spell casts for Nibelung procs. My theory is that the slow effect is considered a cast -- as on Frostfire Bolt, so there's a higher chance. The root of Frostbite may be considered another cast, as may Fingers of Frost. It's possible that a Frost spec would have vastly higher number of spell casts from which to proc Val'kyrs than Fire specs.

As arcane you can use iceblock twice in that fight since it's 10 minutes long. If you only have 1 other dps caster, UM will be up 18-25% of the time. Once mystic buffet is up and you have used your second IB, you'll need to be more careful with you instability stacks. Frost has the WE to dps continually and 4 iceblocks.

Effective dps as arcane in 15 attempts, 2/3 incanters + 2/2 frost warding, Unchained magic 22.4% uptime = 3594

Effective dps as frost, 4 attemptsUnchained magic 19, Unchained magic 21.2% = 2890 Player + 520 WE

I know people think that frost warding + incanters will put arc way ahead of frost. But from my testing it's not that big an advantage a frequent UM debuff. You underrate the advantages frost has in the fight; the WE puts your total damage to about ~95% of arcanes given the group composition. But again this is highly dependent on UM uptime throttling arcane dps.


A note on Nibelung, each blizzard wave has a chance to proc.

Excuse me gents, but I really want to clear this up. Does TtW work on bosses when you frostbolt them? There are a LOT of conflicting answers I found here and on Wowhead and Thottbot.

The last time I used frost was during the valentines boss trio. They are immune to all snares and slows and roots like all bosses, but if you used frostbolt, the slowing debuff would still appear but would NOT slow them. I haven't raided in frost or on my mage in a while so I have no idea if the debuff appears on bosses. So does TtW work its magic on bosses or no?

Following Enthorn's comment: Since a big chunk of your damage depends on a debuff being placed by the tank, it's not a terrible idea to check parses to make sure they are doing so, particularly on fights where your damage seems unusually low or when you're working with a new tank for the first time. In principle any good tank is going to be placing those debuffs but... you never know.

In some cases (warrior Thunderclap) it may be that the warrior isn't applying it; in other cases (Infected wounds) it may be that the tank has a screwy spec. In either case you'd want to know about it if it were happening, because there's much bigger fish to fry than your damage buff.