We've talked about this one a great deal already, but here's the upshot:
Combustion is fire's one long-cooldown DPS ability. The cooldown is only 2 minutes, but this is the only thing you've really got to wait on in your arsenal. Using it well is a bit tricky. It combines all of your existing DoT effects on a single target into one uber-DoT. On the beta right now, it does so without consuming those DoTs, so the talent gives you an additional big DoT. To use it most effectively, you only want to cast it when you have all three of your major DoTs (Ignite, Pyroblast, Living Bomb) already working on your target, and you want the Ignite DoT to be a sizable Pyroblast one, not a puny Scorch one.
I would highly recommend getting a mod for this. The one I use is Combustionhelper. I find it absolutely indispensable.
Improved Hot Streak
Again, we've already discussed this a bit, but let's revisit it. The difference between this and its predecessor on the previous tier is that instead of functioning on a per-spellcast, fluctuating chance of proccing, this improved version has a clear trigger. If you get two consecutive, non-periodic crits with one of your main fire nukes, you get a Hot Streak proc 100 percent of the time. Essentially, as your crit chance improves, this talent ensures that your chances of getting a Hot Streak (and thus a free instant Pyroblast) also improve.
This gives you the ability to cast Scorch while moving. You have to have Molten Armor active for it to work, but every fire mage should really always have Molten Armor active. The cost is that Molten Armor no longer reduces your chance to be struck critically, making this something of a trade-off for PvP mages.
Benefits: It provides you with pretty spectacular mobile DPS. Costs only one talent point. Also, it is awesome.
Drawback: No reduced chance to get critted.
Did I mention that this is awesome?
Here's the aforementioned double-whammy. Whenever you cast a Blast Wave that will hit more than one target (and frankly, why would you ever cast a Blast Wave that wouldn't?), you also get a free Flamestrike on the same location. You get two AoE effects for the price of one! Whoo!
Oh, and this spell also makes your Flamestrikes instant. Which is nice. Like Blast Wave, you may wish to pass on this if you don't think the added AoE damage will help your raid much. If you like AoE, though ... Mmmmm. Tasty.
This gives you another AoE spell, but this one's real benefit comes only in PvP. It's short-range, instant, and damages enemies in a cone in front of you, also applying a 5-second daze effect to those it hits. Plus it looks super cool. Its uses in PvE amount mostly to an "oh crap" button when you have something get too close and need to peel it off you with the daze effect. In PvP, though, it's a powerful tool at close range.
It doesn't really matter, though; every fire mage is taking this one anyway, since it's a prerequisite for Living Bomb.
This one gives you a big fat 12 percent spellpower increase during the final burn-down phase (in other words: precisely when you need it) of every boss. I'm not sure there's anything else to say here, and this column is perilously close to massive-wall-of-text status already. Get Molten Fury.
One more talent that reveals the AoE-centric nature of the fire tree, Pyromaniac gives you a solid 10 percent haste bonus whenever you've got at least three targets taking damage from your various DoT effects, which should be any time there are at least three targets available to you. In single-target fights, this is a waste, but in multiple-target fights, it's awesome. A solid 10 percent haste is a whole lot of haste, and a sizable DPS increase when it's up for two talent points. Some builds will pass on this, but it's worthwhile in any multiple-target build.
Another mandatory talent, this one is a flat 15 percent damage buff to Living Bomb (and later, Flame Orb). In addition, here's where we get our raid-wide 5 percent spell crit debuff. Pyroblast and Scorch apply it, meaning that you'll be beginning every fight with a quick scorch to put the debuff on, but keeping it up over the course of your normal rotation with Hot Streak Pyroblasts.
Come on, it's Living Bomb. Freaking Living Bomb, guys.
Holy crap ... we'd better be done. My fingers hurt, and you're probably done taking a dump by now. Join me next week for a look at the arcane tree.
Every week, Arcane Brilliance teleports you inside the wonderful world of mages and then hurls a Fireball in your face. Check out our recent look at how much I hate damage meters or what to expect for mages in patch 4.0.1. Until next week, keep the mage-train a-rollin'.