Dk Guid!

[Tavari]

First thing's first; Resources

-We have two different resources; Runes and Runic Power.
We have a total of 6 runes namely, 2 Blood, 2 Frost and 2 Unholy Runes. Death Runes are "all purpose" runes that be used in place of any other rune, more on that later.
-Runic Power is generated from used runes and the amount of runic power generated is based on the rune cost abilities, for example, Icy Touch costs 1 Frost rune, and therefore will generate only 10 runic power.
Pretty straight forward on paper. Now we get to how they interact with each other.

At level 60 you'll be able to choose Blood Tap, Runic Empowerment or Runic Corruption which uses runic power to speed up rune regeneration. Effectively, you have to use runes to generate runic power which will in turn help you regenerate your runes. It's a cycle.

Runes begin a regeneration cycle of no more than 10 seconds when used; Haste will decrease this time but not by much.
If more than one of the same type of rune has been used, for example, both Blood runes are used, the second Blood rune will not begin it's cool down time until the first one has finished. The same goes for abilities that cost a combination of runes, e.g Festering Strike used back-to-back will leave the second Blood and Frost rune on empty until the first set has completed it's cool down time. The level 60 talents help speed this process up either by speeding up rune regeneration time (Runic Corruption) or refilling random depleted runes as Death runes (Runic Empowerment, Blood Tap).

Death Coil and Frost Strike cost runic power and will give 2 Blood Charges (Blood Tap talent) per use, or they have a 1.50% chance to activate either Runic Empowerment or Runic Corruption. Note that their runic power costs may differ.

Abilities - How They Work

Each ability a Death Knight has has a rune or runic power cost. Abilities will cost one rune or a combination of different runes, here's the list of abilities that cost only one of a specific rune type. These abilities generate 10 runic power only

-Blood Runes; Blood Boil.
-Frost Runes; Howling Blast, Icy Touch, Pillar of Frost, Path of Frost
-Unholy Runes; Plague Strike, Scourge Strike, Death and Decay, Dark Transformation
-Death Runes; Death Siphon.

The following cost a combination of different runes and will generate 20 runic power when used.

-Blood and Frost Runes; Festering Strike
-Frost and Unholy Runes; Obliterate, Death Strike.
Army of the Dead should be here as well; it costs one of each type of rune (Blood, Frost and Unholy) and will generate 30 runic power.

Let's talk about abilities that cost Blood Runes - these are the single rune cost abilities and as such will only generate 10 runic power use.

-Blood Boil - Damages every enemy within in 10 yards in a circle around you. Probably the most interesting of these abilities because if you choose Roiling Blood (tier 1 talent) you can spread diseases without the need for using Pestilence; for Blood Death Knights it will refresh diseases on all the targets it hits, and for Unholy Death Knights it converts it's Blood rune into a Death rune. As of Patch 6.0.2 it now spreads diseases when it strikes a diseased target.

Abilities that cost Frost runes; again single rune cost only so only 10 runic power will be generated.
-Howling Blast - Area of Effect strike at 30 yard range; will apply Frost Fever to all afflicted targets. Exclusive to Frost spec.
-Icy Touch - Single target version of Howling Blast; weaker in overall magnitude.
-Pillar of Frost - Increases Strength by 20% for 20 seconds; good offensive cool down.
-Path of Frost - Allows you to walk on water; will limit fall damage if glyphed.

Abilities that cost Unholy runes; single rune cost = 10 runic power.
-Plague Strike - single target melee attack that applies Blood Plague; applies both Frost Fever and Blood Plague at level 68 when Ebon Plaguebringer becomes unlocked.
-Scourge Strike - Single target melee attack exclusive to Unholy spec. Main filler attack
-Death and Decay - Targeted area of effect damaging ability.
-Dark Transformation - Exclusive to Unholy, this ability is fueled by use of Death Coils and allows you to transform your active pet/minion into a more powerful creature.

Death Runes - single rune cost = 10 runic power
-Death Siphon - level 75 talent; Single target ranged attack that does damage to your target and heals you a percentage of the damage done.

Blood and Frost - double rune cost = 20 runic power.
-Festering Strike; exclusive to Unholy this ability refreshes and increases the duration of active diseases on a target. Successful Festering Strikes convert its rune cost into Death runes.
-Obliterate; exclusive to Frost this ability is the main attack for a Frost Death Knight using a 2-handed weapon best used with Killing Machine procs for 100% critical damage chance.
-Death Strike; baseline for all specs, this ability heals for no less than 7% of maximum health outside of PvP environments. Activates Blood spec Mastery placing an absorb shield the value of which is equal to the percentage of the Mastery stat when Death Strike heals you.

An example of Death Strike and Blood spec Mastery; if I have 200% mastery and Death Strike heals me for 300k that means I'll get 200% of 300k as an absorb shield for 10 seconds; I'll also get a certain percentage of that as Attack Power.

Runic Power - will store Blood Charges for use of Blood Tap or activate Runic Empowerment or Runic Corruption.
-Death Coil; usable for Blood and Unholy spec. It's a ranged attack, but can be used in conjunction with Lichborne (tier 2 talent) to heal yourself. Can be used on your active pet to heal it. As Unholy it'll give the buff called Shadow Infusion to your pet which, at 5 stacks (5 Death Coils), will allow for Dark Transformation which "enrages" your pet making it more powerful. As Blood spec it's just a runic power dump and should be used when you're running low on runes in order to proc your level 60 talents.
-Frost Strike; exclusive to Frost spec, single target melee attack.

Death Coil and Frost Strike are often best used when you're at, or approaching, 100 runic power, but are ideally used when spaced out across your "rotation" which brings me neatly to the next part of the guide.

Abilities - What to use and When
This is in itself a full guide all on it's own, but if you can work with a clear picture of the cycle, runes > runic power > runes, you should do alright; I highly recommend the addon called CLC DK which you can download from here : http://www.curse.com/addons/wow/clc-dk

This addon, with the exception of Blood spec, will allow you to monitor the cool down and affects of different abilities and will display what action you should use next to maximize DPS. I've found it ineffective for Blood spec as Blood is for Tanking and doing maximum DPS isn't always a priority for tanks. I recommend it for beginners as it'll help you get an idea of what abilities you could be using and when. It should help you learn the rhythm of your chosen spec but do keep in mind that it doesn't take into consideration the current encounter be it AoE or heavy movement fight.

If you can stand listening to the man I recommend Preacher's guide on Blood Tanking found here; they are out of date but the spec still plays very similar to how he describes. If anything it'll give you a place to start and develop your own style of play with.