When you take a look at the changes as a whole, they boil down to a surprisingly elegant solution to a few problems. Unholy comes out the least changed with this. The extra rune regen and haste should keep them from having too many free GCDs, and otherwise, everything continues more or less as before. Where this really gets interesting is with frost.
Frost mixes things up
Two-handed frost, of course, appears to lose a lot with this change. With all that runic power regeneration going away, much of what made two-handed frost "playable" seems to be gone. Luckily, what we've received in return more than makes up for it. The runic power reduction to Frost Strike's cost means we're still good to go on runic power. That said, Obliterate's damage increase means we're not even concerned about Frost Strikes as much, except as a way to trigger our rune regeneration. After of course hit and expertise ratings, a two-handed frost death knight is going to want to stack haste and keep diseases up to make Obliterates hit as hard as possible. You'll especially want to make sure you save your Killing Machine procs for Obliterate whenever possible.
Dual wielding, on the other hand, gets a shift to focusing on Frost Strike and through that, frost damage. Whereas before, dual wielding DKs lagged behind two-handed frost in runic power regeneration, they should now be equal, and since Threat of Thassarian has that Frost Strike damage increase, you should be focusing on those Frost Strikes, using your Killing Machine procs for them and stacking mastery to make them hit harder. As a side effect, this also ends up making dual-wield frost the AoE DPS spec due to harder hitting Howling Blasts.
A few nagging issues
There are, of course, a few kinks to work out even with these new presences. The removal of Threat of Thassarian's off-hand damage bonus seems to have mostly closed the gap with two-handed frost for now, but two-handed frost is still in the precarious position of just plain not scaling as well. It remains to be seen if super-buffed Obliterate will work. For dual wielding, the fact that they focus on Frost Strikes means they can almost completely ignore Blood Plague, which is a state Blizzard has not been happy with in the past. If we see too many death knights skipping Blood Plague, expect some adjustments to fix that.
Another problem comes with the interaction of the strike damage bonuses. Since all frost death knights get both Threat of Thassarian and Might of the Frozen Wastes now, getting a different strike bonus is as simple as switching your weapons. In theory, then, you could use a simple weapon switch macro to get hard hitting Obliterates and hard-hitting Frost Strikes. Luckily, switching your weapons triggers a cooldown of its own, and that seems to be restrictive enough that it's not worth it to do for PvE DPS, especially with the stat weight differences. It may be a different story for PvP, and we may have to brace for some nerfs if weapon swapping proves more useful there.
The issue of how many free global cooldowns is too many also continues to come into play. The 1-second global cooldown becoming universal helps this a lot, but there's still some murmurs in the death knight community that we have too much downtime. In the end, we should probably accept that we'll never have our old levels of runic power generation back, but multiple seconds of downtime aren't much fun either, in theory. This is something we'll probably need to keep a closer eye on as we test, parse, and run sims. How much actual downtime do we have, and is it too much?
Finally, of course, this doesn't solve our rune regeneration skill issues. Currently, Blood Tap is easily the best of the rune regeneration skills, and to make matters worse, you can get almost optimal use out of it by simply macroing it to your runic power dump. Since it doesn't trigger a GCD, you can simply add it on with the strike, and it will give you a Death Rune every time you have enough charges saved up, ready to be used on Soul Reaper or anything else.
Still, this presence change goes a long way to helping with a few of our issues, and it should make the class a lot more fun and a little smoother to play going into Mists of Pandaria. With the class balance beta feedback thread still in full swing, we can hope that Blizzard takes notice and gets a few more of issues solved before beta is up, and with any luck, we'll still be in a good place when Mists goes live. Until then, get those Blood Tap macros ready.
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