Recently I’ve been doing two major things in WoW: 10-man hard modes and trying out Blood DPS in raids. While the DPS itself is not significantly higher or lower than Frost for most fights, some of Blood’s unique mechanics help out a lot for hard modes, especially ones like Mimiron, Thorim, and Freya, where you will likely take significant amounts of incidental damage throughout the fight. (Frost is better for Hodir due to the many crits produced by Rime, Killing Machine, and Subversion.)
So first I want to outline what Blood has that the other specs don’t have (or have less of):
1. Self-healing. All classes have Death Strike but since it’s in Blood’s main rotation, you not only gain more health from it but also lose less DPS from choosing to cast it over something else (like Obliterate or Scourge Strike).
2. Diseaseless damage. Before you get all up in arms about me and say that diseaseless Blood is dead, the only disease-dependant attack in Blood’s rotation is Heart Strike. What this means for hard modes is that, when you need to quickly mow down a low HP target, like Freya’s roots, Thorim’s Evokers, frozen people in Hodir and various adds in Mimiron, you don’t always need to set up diseases to do decent damage. Frost without Frost Fever up does very little damage (losing 15% from Tundra Stalker and another 20% from Glacier Rot) and Unholy loses 10% from Rage of Rivendare as well as the additional scaling from diseases on Scourge Strike.
If you set Blood up correctly or get lucky, i.e. if you have lots of RP or simply enough RP to maximize Death Strike damage with the glyph, you can hit things like Freya’s roots without wasting a valuable GCD on PS/IT to set up your damage. This might seem minor, but it really helps out a lot when time is limited (Mages die very quickly to roots!).
3. Burst damage. Combining DRW + Hysteria gives you a very potent burst rotation, and you also get DRW every 1.5 minutes. Unholy only really has Gargoyle (on a 3min CD) and Frost only has UA, which unfortunately combines a defensive and offensive cooldown, meaning you may use it for one purpose and later need it for the other. (Blood gets a choice between Vampiric Blood, Mark of Blood and Rune Tap as well, which helps out with its survival.) Burst is very helpful for hard modes are either DPS races (Hodir) or have short phases that require burst damage (XT) (Freya’s various adds).
4. Heart strike hearts you. The mechanics of Heart Strike are very nice (well, not for Hodir or Thorim much), mainly for Freya and Mimiron. On Freya, the 3-elemental phase (in 10-man anyways) often leaves you well away from the Snaplasher but close to the other two elementals. What this means is that you will be HSing both at once, and no other spec can really hit two targets for 5-6k consistently (Howling Blast has a cooldown, UB does damage over a longer period of time, Death and Decay takes time and lots of runes). On Mimiron, you get to smack two sections for lots of damage.
Hard mode is hard
I’ve done this fight as Frost. It wasn’t incredibly easier with Blood than Frost, but I definitely noticed the perks I’ve outlined here. One other minor benefit that Blood gets is 6% more stamina from Veteran of the Third War, which isn’t a big deal but it’s definitely a perk to have 30k+ HP in DPS gear. The best thing Blood has going for it in hard modes is that you can keep yourself alive very well.
For additional survival, you could spec into Night of the Dead for the ability to Death Pact more often, since you only lose 2 points in BCB to take it. This is useful for Freya, where damage is spiky but not continous, so you’re likely to have time to get the two GCDs necessary to summon and pact the ghoul. Unfortunately it’s less useful for more bursty fights like Mimiron, where damage happens at every turn.
So if you’re working on hard modes, and aren’t already Blood, give it a try.