Blood death knights get the most out of the three trees from Armor Penetration on gear, as blood abilities magnify weapon damage rather than dealing as much shadow or frost damage. Blood Strike is replaced entirely by Heart Strike in almost any situation (unless it's really important not to do any AoE damage at all) as HS does more damage to its primary target and also hits a secondary. Death Strike, meanwhile, takes the place of Obliterate or Scourge Strike. Although it's true that Frost and Unholy DK's have access to Death Strike, they're only using it for its self heal most of the time, while you will most likely use it when Heart Strike is unavailable as a part of your damage rotation. Death Strike is also useful for a tanking DK both for the obvious use in helping reduce the healing load while tanking, but also for the added threat from the self heal (which is further modified by Frost Presence). You'll notice that Death Strike is also based on weapon damage and is not converted to shadow or frost damage, so it also benefits from ArP.
Most of the time I use a variation of 51/0/20 for my DPS spec. This is the current variation I use, although I tinker with it fairly often to see what I like or dislike. I prefer Vampiric Blood to Will of the Necropolis, for example, even though both are more defensive than offensive abilities, as I prefer abilities I can choose to make use of over ones that go off by themselves. This build relies in great part on the synergy between Bloody Vengeance, Blood Gorged, Sudden Doom, Might of Mograine and Hysteria. Bloody Vengeance stacks after each crit, giving you up to 9% more physical damage dealt. Blood Gorged increases your armor penetration by 10% as well as increasing all physical damage when you're above 75% health. Meanwhile, the critical hits you're using to stack Bloody Vengeance hit harder thanks to Might of Mograine, and you're almost certainly using Heart Strike to proc Sudden Doom Death Coils, while benefit from your Morbidity over in unholy. Also, with Improved Death Strike, you not only do more damage (30% more) you also have an extra 6% chance to crit, making it easier to stack up Bloody Vengeance. And of course you can always throw Hysteria on yourself for even more physical damage.
However, blood also has some truly impressive tanking talents in its arsenal. Blade Barrier is easily available to any tanking DK and is as much a must have ability, in my opinion, as Anticipation or Toughness. Bladed Armor, while certainly useful to a DPS DK, takes advantage of a stat most tanks are going to try and get a lot of anyway.Death Rune Mastery is another of those 'good for anyone, great for tanks' talents that I pretty much take whenever I can get it to convert frost and unholy runes to death runes I can use for abilities like Rune Tap. Improved Rune Tap means you can get 20% of your maximum health every 30 seconds (Sadly, the Rune Tap Glyph only adds an underwhelming 2% of your health when used with Improved Rune Tap, as it adds 10% of the ability's effect, or 2%, making it meh unless you're really interested in healing your party when you use Rune Tap.) I personally like Mark of Blood for tanking, although with points being at a premium I often skip it in favor of Imp Rune Tap and Vampiric Blood. I just can't say no to a Last Stand that also increases healing effects on me. If you don't like to keep track of cooldowns, Will of the Necropolis is a good option. I personally prefer watching my abilities and using them when I believe I need to rather than letting them run themselves, but this is absolutely a strong ability.
Combined with Improved Blood Presence and Improved Death Strike, a blood DK can marshal a lot of self-healing with this spate of abilities. Chaining an improved Rune Tap, Vampiric Blood and Mark of Blood while using Death Strike a Blood DK can go from almost nothing to full health in a few GCD's.
If up until now you've stayed primarily within Frost or Unholy, I'd really recommend giving Blood a try. It's a different type of DK... less Howling Blasts and Killing Machine style magic damage, less pet management, less reliance on shadow damage (although it should be admitted that most DPS blood DK's go up to get Necrosis and Blood Caked Blade) and more stacking physical damage buffs and unrelenting self healing. What could possibly be better than using your enemies' own vitality, their very life force, against them?
Welcome to Lichborne, the new class column on the new WoW class, the Death Knight, where we discuss Patch 3.1 cookie cutter builds, basic defense gear and Heroic defense gear for the Death Knight tank, 5-man Crusader's Coliseum gear previews for tanks and DPS, and basic Death Knight statistics and mechanics. You might also want to check all the other articles in our Death Knight category.