Unholy Death Knight two-hand raiding compendium

This is a guide made for unholy 2hand dpsers. Some of the points may apply to other specs as well but this cannot be guarenteed.

Table of Content
- Why would you bring an Unholy Death Knight?
- Skills
- Talents
- Glyphs
- Optimal speccs
- Gear Selection
- Gems
- Enchants
- Consumables


Why would you bring an Unholy Death Knight?
Unholy Death Knights are very valuable for a raid as they bring the fastest and most efficient way of increasing spell damage vulnerability on a number of mobs by 13%. Moonkins bring the buff as well but they can't spread it to a number of mobs as fast as Death Knights can do it through Pestilence (see below for description).
Another reason to bring an Unholy Death Knight is the Unholy Aura that increases run speed by 15% for the entire raid. This can be very valuable on fights that require movement, such as Heigan or fights where you need to move out of AoE asap.This will be removed in 3.1 though.

Last but not least Unholy 2hand specs have a really high personal dps which in it self justifies a raid spot. Only catch is that having two unholy 2h Death Knights in the raid synergies rather poorly as they can't both have 3 diseases on the target which means that one of them will lose some dps.

Skills


Plague Strike
A strike dealing 30% weapon damage plus 113. This ability infects the target with Blood Plague which is one of your three diseases. This ability costs 1 Unholy Rune.
This ability is used solely to apply Blood Plague as the damage is too low to be of any use. Blood Plague is very important though as it increases damage taken from your special attacks by 10% on the target through the talent Rage of Rivendare, so the ability is not to be neglected.


Icy Touch
A spell that deals 227 to 245 frost damage (+ 0.1 per AP) and infects the target with Frost Fever. This is your second disease. It costs 1 Frost Rune.
This ability hits for roughly twice as much as Plague Strike even untalented. It's still only used for applying Frost Fever as the use of a Frost Rune on Icy Touch means fewer Scourge Strikes (see the talent section below).


Blood Strike
A strike that deals 50% weapon damage plus 191 and an additional 95.5 damage per disease on the target. This ability costs 1 Blood Rune.
Blood Strike in itself deals decent damage but it's main use is to convert the Blood Runes into Death Runes that can later be used on a Scourge Strike.


Pestilence
Deals 65 to 79 shadow damage (+ 0.04 per AP) to all enemies within 10 yards and spreads any disease on the target to all targets within 10 yards. 10 seconds cooldown. Costs 1 Blood Rune.
The damage from Pestilence is decent, but it's use is to quickly spread your diseases to all targets in order to do efficient AoE. This synergies very well with the Wandering Plague talent discussed later. By spreading Blood Plague to all targets, your AoE will deal an additional 10% damage to the targets due to the Rage of Rivendare talent.


Blood Boil
Deals 117 to 143 shadow damage (+ 0.0635 per AP) to all diseased enemies within 30 yards. Costs 1 Blood Rune.
This is not an imba dps ability, but it's the only use of your blood runes when AoEing (after having used Death and Decay) and you already have diseases ticking so it's adviced to use it anyway.


Death and Decay
Death and Decay deals 62 shadow damage (+ 0.023 per AP) every second to enemies within 10 yards. Lasts for 10 seconds. This ability causes a high amount of threat. The ability costs 1 Blood, 1 Frost and 1 Unholy Rune.
Death and Decay is a quite effective AoE and should be kept up as much as possible when AoEing. On typical trash packs they die too fast for you to refresh D&D and get full effect of the ability so refreshing D&D doesn't happen all too often. With Morbidity (is in all dps specs) D&D has its cooldown reduced from 30 secs to 15 secs.


Death Coil
Ranged attack dealing 443 shadow damage (+ 0.15 per AP) to an enemy target or heal a friendly undead target for 664.5. 30 yards range. Costs 40 Runic Power.
Death Coil is the ability you'll find yourself using the most to dump your runic power. This does not mean that it is the prio when it comes to dumping Runic Power (this will be Unholy Blight (see under talents)). Death Coil hits hard and is a "free" ability in the sense that you can use it when your Runes aren't available so it is well worth using. The Death Coil damage is increased by 15% from the Morbidity talent mentioned in the Death and Decay section.


Horn of Winter
Increases the Strength and Agility of all party members within 30 yards by 155. Lasts for 2 mins. The ability also generates 10 Runic Power. Cooldown is 20 seconds.
This is the Death Knight's equivalent to the Shaman's Strength of Earth totem. Therefore it does not stack with said totem, but using it allows the shaman to use another totem from the Earth school. This buff should be kept up at all times. Shamans have the option to spec to improved totems though which makes their totem stronger than Horn in which case the buff cannot be kept up. It is still worth using it though if you got some downtime where all your runes are on CD, your Bone Shield is up and you don't have enough Runic Power to cast a Death Coil. This way you generate 10 Runic Power.


Blood Tap
Immediately activates a Blood Rune as a Death Rune for 20 seconds at the cost of some health. 1 min cooldown.
This ability can overall be used in two ways: 1) As a direct damage increase by using it right after having used your two Death Runes on a Scourge Strike which will activate 1 of the 2 used runes as a Death Rune and you can smack a Blood Strike to consume it again. This gives you a "free" Blood Strike except for the Global Cooldown (GCD) used. It does not penetalize you on the CD side as the 2 Blood Runes will be used as Blood Stikes in next rotation which means that they don't have to activate at the exact same time.
2) Or you use it to keep up your Bone Shield. Bone Shield costs 1 Unholy Rune and would therefore normally cost you a Scourge Strike to refresh, but instead of sacrifising an Unholy Rune you can convert a Blood Rune into a Death Rune and use this to refresh your Bone Shield. The timing of the Death Rune should be as mentioned above.
A combination of these two suggestions are to be prefered, where keeping Bone Shield up is priority.


Empower Rune Weapon
Immediately activates all your Runes and generates 25 Runic Power. 5 min cooldown.
this ability is very useful in two situations. 1) Burst damage where you use it right after you've put all your runes on cooldown in order to activate them all instantly or 2) save your Gargoyle in case you're running low on Runic Power and can't build up enough Runic Power from Runes fast enough.
Personally I use it solely as number 1. When a rotation is performed right and you are careful with Death Coils you will not be in a situation where your Gargoyle is dying prematurely, so number 2 should not be an issue in normal dps situations. Timing it with trinkets is very effective since it allows you to put out more attacks under the effect of increased AP.


Rune Strike
A strike that deals 150% weapon damage plus 0.15*AP. It can only be used after you dodge or parry, and the attack can't be dodged, blocked or parried. Causes a high amount of threat. Costs 20 Runic Power.
This ability is the highets damage per Runic Power for a Death Knight and should be used whenever possible. It is sadly not available often as it requires you to dodge or parry an attack, but since it does not cause a Global Cooldown (GCD) it can be macroed to all your attacks and used when available. Such a macro would look like this:

#showtooltip
/script UIErrorsFrame:Hide()
/cast Scourge Strike
/cast Rune Strike
/script UIErrorsFrame:Clear(); UIErrorsFrame:Show()

The two scripts simply ensures that your Error Frame isn't flooded with "Not ready yet" messages.


Army of the Dead
Summons a legion of ghouls that taunts and attacks all enemies around them. While channeling the spell you take less damage equal to your dodge + parry chance. Cooldown 20 mins. Costs 1 Blood 1 Frost 1 Unholy Rune.
As the description says, the ghouls taunt the enemies around them and thus they can be rather annoying for tanks when used on trash. But bosses are immune to the ghoul taunt and therefore the Army can freely be used on bosses for a substantial dps. The ghouls scale with your current AP and should therefore be used in conjunction with with trinkets etc if possible. If the encounter involves high raid damage, make sure to use the Army just after such an AoE has been cast in order to avoid them dying instantly. Not all encounters are suitable for Army though. An example of such a fight is Heigan where they die almost instantly and it is therefore a waste of runes. Also considering the cooldown it's much better to save the ability for the next boss (Loatheb) which is a much better encounter for Army.


Death Strike
Deals 60% weapon damage plus 178.2 and heals you for a percentage of the damge done for each of your diseases on the target. Costs 1 Frost and 1 Unholy Rune.
You will probably not find yourself using this ability a whole lot in raiding as its damage is very low compared to Scourge Strike and it costs the same. It can be useful though if you are taking heavy damage and your healers can't keep up with it. In far most situations relying on the healer to do his job is better for the raid as a whole


Anti-Magic Shell
Creates a shell around you absorbing 75% of all magical damage done to you and prevents application of harmful magical effects. Damage absorbed generates Runic Power for you. Lasts for 5 seconds. Cooldown 1 minute. Costs 20 Runic Power.
Anti-Magic Shell is different from the other abilities mentioned here as it is mainly a defensive utility rather than a damage increase. It can, however, be used to increase your damage some. If some phases of a boss causes very high damage to the raid you can use AMS to give you alot of free Runic Power at no cost (provided the aoe is unavoidable). Even avoidable AoE can in some situations be reasonable to take if you need the Runic Power to, say, keep your Gargoyle from leaving prematurely, or if you just need more Runic Power to do some ranged damage. And example of this could be Heigan where it is possible to pop AMS and take one of the green flames in order to generate alot of Runic Power that can be used on Death Coils during the dancing phase. The damage you take will be minimal and it helps getting him down faster. Using AMS in this way is never a must though, but I simply wanted to let people know that it is an option if one feels like it.

Talents

In this section I will discuss the talent choices you phase when speccing as an Unholy 2h dps DK. Each talent has its description shown and a discussion of its usefulness. I will leave out the following talents as these are obviously not worth taking: Anticipation, Unholy Command, On A Pale Horse.
I will also include the top Blood talents which are the ones you will be filling up with after reaching the desired amount of Unholy talents.

Unholy

Vicious Strikes - 3 talents
Increases the critical strike chance by 3/6/9% and the critical damage bonus by 15/30/45% of your Plague Strike, Scourge Strike and Death Strike.
This is a must have talent for any unholy spec (and also most other specs), if not only for the lack of other options As Unholy the increases crit and crit dmg bonus on Scourge Strike from this talent is amazing and you really can't live without it.

Morbidity - 2 talents
Increases the damage and healing done by Death Coil by 5/10/15% and reduces the cooldown of Death and Decay by 5/10/15 seconds.
This as well is a must have talent. Death Coil will normally do around 10% of your total damage so although an overall 1.5% damage increase for 3 talents is rather low considering the standard 1% damage increase per talent budget the alternative is 3% dodge which is pretty useless. The reduced cooldown on Death and Decay also has its uses when AoEing.

Epidemic - 2 talents
Increases the duration of your Blood Plague and Frost Fever by 3/6 seconds.
This talent is also oen to take as it increases your diseases' duration to 18 seconds which means that you don't have to refresh them every rotation but just every second rotation. This allows for an extra Scourge Strike every second rotation. Thats roughly 2k more damage every 20 seconds = 100 dps = 50 dps / talent point. Well over the budget 1% budget.

Virulence - 3 talents
Increases your chance to hit wit spells by 1/2/3% and reduces the chance that your diseases will be cured by 10/20/30%.
This is a decent talent. When you cap your melee hit at 9% you only have 11.3% spell hit, so you still need a bit of hit to cap your spells (17% on raid bosses, 14% with shadow priest or boomkin) and spells are not neglectiable as an Unholy dk. Virulence will leave you just over 14% spell hit which means that you are then capped on spell hit when you raid with a boomkin or shadow priest. Affected spells are: Icy Touch, Death Coil, Unholy Blight, Pestilence, Blood Boil, Death and Decay, Wandering Plague and Strangulate. It is a good talent to return to and put points in to reach new Tiers of talents. I would recommend capping this talent as the alternatives are questionable in dps and it will afterall affect around 20% of your single target rotation's dps.

Ravenous Dead - 3 talents
Increases your total Strength by 1/2/3% and the contribution your Ghouls get from your Strength and Stamina by 20/40/60%.
Again a must have talent. It will substantially increase your pet's damage as well as give yourself a nice boost. THE best stat to stack for a Death Knight is Strength so you will find yourself with alot of it. Increasing it by 3% is a quite nice boost.

Outbreak - 3 talents
Increases the damage of your Plague Strike and Blood Boil by 15/30/45%.
At first this talent may sound enthralling as 45% damage sounds like alot. Reality is though that plague strike is used AT MOST every 2nd rotation and it doesnt hit for much. Plague Strike will typically be 2% or less of your dmg and spending 3 talent points on increasing that by 45% is obviously not a good investment.
The AoE aspect of the talent is somewhat limited as well since blood boil is your poorest AoE and can only be used 1.5 times on average per rotation (10 seconds), since you need to use 1 Blood Rune on Pestilence every other rotation.

Necrosis - 5 talents
Your auto attacks deal an additional 4/8/12/16/20% shadow damage.
This is a decent talent. What it really does it to hit the target with a seperate spell called Necrosis dealing damage equal to 20% of the damage your auto attack hit for. But since this is shadow damage it scales with Ebon Plaguebringer so it gains the +13% damage from this. This means that the actual effect of the talent is 22.6% damage. Auto attacks will typically be 25% of your damage and thus this talent will give you a 5.65% damage increase. Worth taking.

Corpse Explosion -1 talent
Causes a nearby corpse to explode for 443 (+ 0.19 per AP *) shadow damage to all enemies within 20 yards. Does not affect mechanical or elemental corpses. 5 sec cooldown. Costs 40 Runic Power.
This ability is a hardhitter when AoEing, especially if glyphed (see the glyph section). Only problem with this ability is that it requires something nearby to be dead. When AoEing the mobs tend to die at roughly the same time (or at least be rather low on health when the first mobs die) which means that it often won't get the mobs down much faster. There are ofc situations where this is not the case, or where you kill pack after pack at the same spot and in these situations it is a very strong AoE ability. Whether to take it is a matter of personal preference. Should you choose to take it it will most likely be at the cost of a point in Virulence of Blood-Caked Blade (see below).

*The coefficient is unconfirmed and based on a very small sample, performed by me.

Blood-Caked Blade - 3 talents
Your auto attacks have a 10/20/30% chance to cause a Blood-Caked Strike that hits for 25% weapon damage plus 12.5% for each of your diseases on the target.
This ability hits for 62.5% weapon damage when you have 3 diseases on the target. This isn't bad, but the fact that it only procs 30% of the time makes it somewhat uncool. When you look over WWS logs you find that BCB generally deals 3% of your total damage. So yes, it deals the standard 1% damage increase per talent point, but the alternatives are much more desireable, such as Necrosis or Shadow of Death, or even Virulence. Nonetheless is it a good talent take in order to reach next tier of talents, and thus most builds will include 2 or 3 talents in this. Should you need a talent for something else though, BCB should be the first place to take it from if possible.

Shadow of Death - 1 talent
Increases your Stamina and Strength by 2% and when you die you are returned to fight as a Ghoul for 25 seconds. Cannot occur more often than every 15 minutes.
Being returned as a Ghoul when dying is fun and makes it possible to dps for a while after dying, but the main reason to take the talent is the increased Strength. 2% Strength for 1 talent point is pretty good and getting 2% Stamina and the ability to keep figthing while dead makes it an excellent choice for 1 talent point.

Summon Gargoyle - 1 talent
Summons a Gargoyle that will blast the enemy with damage for 10 seconds plus 1 second per 8 Runic Power up to 30 seconds. Cooldown 3 minutes. Costs 50 Runic Power.
The Gargoyle deals damage equal to 40% (50% with Impurity talent) of your AP at the time of summoning it. It means that when you click the button it takes a snapshot of your current AP and will use that AP for its entire duration. This means that it should be used when you have the highest AP possible. Let's take a 5 min boss fight as an example: Wait for Fallen Crusader to proc (+30% damage) then pop any trinkets you might have increasing your AP and then pop your Gargoyle. Considering the high proc chance on Fallen Crusader this is very likely to happen within the first minute which means that Gargoyle will be ready again once more later in the fight and you can do the same then. This is a MUST HAVE talent for any Unholy spec, as it easily reaches 1500 dps while up and it can be pushed to a 1/6th uptime. Let's shoot low and say 200 dps for 1 talent point. Can't miss that.

Impurity - 5 talents
Your spells recieve an additional 5/10/15/20/25% benefit from your attack power.
This is an excellent talent as it affects all your spells by quite a bit. Affected spells are: Icy Touch, Frost Fever, Blood Plague, Gargoyle, Death Coil, Pestilence, Death and Decay, Blood Boil and Strangulate. This talent should be maxed.

Dirge - 2 talents
Your Death Strike, Obliterate, Plague Strike and Scourge Strike generates 2.5/5 additional runic power.
This talent generates a hell of a lot of Runic Power for an unholy Death Knight as you will find yourself spamming alot of Scourge Strikes. With this talent Scourge Strike generates 20 Runic Power (up from 15) and 30 Runic Power if you have the 4/5 t7 set bonus. With that you can build up 90 Runic Power on every second rotation which allows you to cast more Death Coils (even when having Gargoyle up) and thus increasing your damage substantially. Death Coil is your 3rd strongest ability so getting more of these off is a major plus. On average the ability gives you 12.5 (2.5 Scourge Strike/Plague Strike per rotation) every 10 seconds = 1.25 RP/sec. This means that it takes 32 seconds to generate an additional Death Coil. Assuming an average damage of a Death Coil on 4k it equals to : 3500 dmg / 32 seconds = 109 dps = 54.5 dps / talent point. Unholy DKs arent as limited on Global Cooldowns as other specs so fitting in the extra Death Coil shouldn't cause you original rotation to lose any dps.

Magic Suppression - 5 talents
You take 1/2/3/4/5% less damage from all magic. In addition, your Anti-Magic Shell absorbs an additional 5/10/15/20/25% of spell damage.
This is a pvp / tank talent (not even sure I'd take it while tanking). 5% less magic damage taken is useless for a dpser and while the other effect allows your AMS to absorb 100% spell damage making you effectively immune to magic while it is up, it is not even remotely worth 5 talent points. The only reason to take it would be to get Anti-Magic Zone (see below).

Reaping - 3 talents
Whenever you hit with a Blood Strike or Blood Boil there is a 33/66/100% chance that the spent Blood Rune will become Death Runes when it activates.
This is an essential talent as well as it allows you to replace the 2 Blood Strikes with a Scourge Strike in every 2nd rotation. Let us assume an average damage on Blood Strike of 1720 damage (including crits). This this equals to 3440 damage from the 2 Blood Runes. Scourge Strike equals around 4k on average (including crits, considering the increased crit damage and crit chance). This leaves you with 560 damage extra every 20 seconds = 28 dps = 9.33 dps / talent. In addition to this comes an extra GCD that can be spend on a Death Coil or Horn of Winter and it gives you an extra chance to proc the Scourge Strike glyphs, which when proccing increases your damage significantly. Lastly you also generate an additional 10 Runic Power if you got 4/5 t7.
The numbers used in the calculations are based on a WWS log from 16th March and Godsbane's stats.

Master of Ghouls - 1 talent
The Ghoul summoned by your Raise Dead spell is considered a pet and is under your control. Unlike normal Death Knight Ghouls, your pet does not have a limited duration.
This talent is also called perma-pet which means that it lets you have your pet up at all times (provided it doesn't die from damage). This alone is a significant increase in damage as your pet hits pretty hard and you are no longer limited by the 2 min duration and 5 min CD. Additionally it allows you to control your pet which means that it's alot easier to keep it alive and to make sure it doesnt do stupid stuff that might wipe the raid. You can expect your Ghoul to deal 600+ dps in raids. Without Master of Ghouls this would only be 240 dps (2/5th of 600). So a net dps increase of 360 dps from 1 talent!

Desecration - 5 talents
Your Plague Strike have a 100% chance to cause the Desecrated Ground effect. Targets in this area are slowed by 50% while you cause 5% additional damage while standing on the unholy ground. Lasts 12 seconds.
At first this sounds like a really nice talent. 5% increased damage, huh? This is not the case. First off it only procs on Plague Strikes which are only used every 2nd rotation, max. Often it's even less due to Scourge Strike glyph procs. While you could skip Epidemic, take outbreak and desecration and use Plague Strike in every rotation, theory crafters have several times shown that this isn't optimal. Let's just assume that we use Plague Strike every 30 seconds (every 3rd rotation). This is a 40% uptime which means that you only get 2% damage increase from the 5 spent talents. Additionally it requires you to stand on the ground to get the effect, which on several encounters will be hard to maintain due to the need to move. The slowing effect from Desecration is trivial in raids. This talent does not justify spending 5 talent points that could be spend alot better.

Anti-Magic Zone - 1 talent
Places a large, stationary Anti-Magic Zone that reduces spell ddamage done to party or raid members inside it by 75%. Lasts 10 seconds or until it has absorbed 10,000 ( + 2 * AP) spell damage. 2 min cooldown. Costs 1 Unholy Rune.
This talent is nice to occasionally help healers on heavy aoe spell damage. But the fact that you can only use it every 2 mins and it requires you to spend a whole 6 talent points on it (Magic Suppression is required) it is not viable to take in a dps spec. Leave the healers to worry about keeping people alive and focus on your job: The damage dealing. A Disc priest can in 5 seconds cast shields on people absorbing as much damage as the AMZ so with some foresight you have no need for the AMZ (after 3.1).

Unholy Aura - 2 talents
All part or raid members within 45 yards move 8/15% faster. This effect does not stack with other movement improving effects.
This is a very nice ability as it allows the raid to run faster from trouble (such as Heigan) and is one of the reasons to bring an Unholy Death Knight. The alternatives provide rather limited damage (Desecration being the main alternative) which makes the points best spend in Unholy Aura.

Night of the Dead - 2 talents
Your next 10 Plague Strikes and Scourge Strikes lower the cooldown of raise Dead by 15/30 secs and Army of the Dead by 30/60 secs per Strike. Also reduces the damage your pet takes from AoE attacks by 40/70%.
This talent is incredibly valueable in situations with AoE damage. Not only allows it to keep up your pet up close to 100% of the time, but it also reduces the damage your pet takes, lowering the need to resummon / healing it. Without it you lose alot of damage from your pet in situations that involves AoE. This talent should be maxed (again the alternative is Desecration).

Crypt Fever - 3 talents
Your diseases also cause Crypt Fever, which increases disease damage taken by the target by 10/20/30%.
This not only increases the damage of your own diseases but also everyone else in the raid's diseases. Additionally it counts as a disease by itself which means that Scourge Strike and Blood Strike will deal additional damage with this talent. It also leads to Ebon Plaguebringer which is THE most important talent as an unholy DK which means that this talent is a must.

Bone Shield - 1 talent
You are surrounded by 4 wirling bones. While at least 1 bone remains, you take 20% less damage from all sources and deal 2% more damage. Each damaging attack that lands on you removes 1 bone. Lasts 5 mins. 1 min cooldown. Costs 1 Unholy Rune.
Bone Shield is a must have talent. The 2% damage increase is very nice for 1 talent point and the reduced damage taken is a nice bonus. The only problem can be to keep Bone Shield up. In order to avoid losing a scourge strike everytime you want to renew Bone Shield you will typically use Blood Tap to renew it. Read more about this in the Blood Tap section in "Skills".

Wandering Plague - 3 talents
When your diseases damage an enemy, there is a chance equal to your melee critical strike chance that they will cause 33/66/100% additional damage to the target and all enemies within 8 yards. Ignores any target under the effect of a spell that is cancelled by taking damage.
In a single target fight this talent essentially allows your diseases (Frost Fever and Blood Plague) to crit. Let's say you have a 35% crit chance, then you get a 35% increase in damage on Blood Plague and Frost Fever. These 2 will typically be around 10% of your total damage combined, meaning a 3.5% damage increase for 3 talent points. So even in single target fights this talent is worth taking. Even more so in AoE where all your dots ticking on all mobs have a chance to proc Wandering Plague, dealing damage to all mobs around them. This deals alot of damage even though there seems to be an internal cooldown on how often the ability can proc.

Ebon Plaguebringer - 3 talents
Your Crypt Fever morphs into Ebon Plague, which increases the magic damage taken by 4/9/13% by the target in addition to increasing disease damage taken. Also improves your critical strike chance with weapons and spells by 1/2/3% at all times.
THE best talent in the unholy tree and the main reason a raid brings an unholy Death Knight. This talent not only increases your own damage substantially (Death Coil, Icy Touch, Scouge Strike, diseases, Unholy Blight etc), but also all other spell casters in the raid. This debuff is a must have for any raid. In single target fights a Moonkin can provide it as well, but no class can bring it as effectively to AoE fights as unholy Death Knights can with Pestilence.
Currently (3.0.9) there's an issue with Ebon Plaguebringer which means that 2 Death Knights can't both have Ebon Plaguebringer on the target which means that one of them loses the bonus of having 3 diseases on the target. Blizzard have stated that they will fix this at some point, but it is not their first priority. Before patch 3.0.8 it was possible for the 2nd unholy Death Knight to only spec to Crypt Fever and then apply that buff to the boss and then getting the bonus from 3 diseases (skipping Ebon Plaguebringer), but this was changed in 3.0.8 as it turned out that Ebon Plague and Crypt Fever stacked the diseases damage increases so Blizzard chose the quick solution, not allowing Crypt Fever to be on a target with Ebon Plague, effectively killing the last chance to have 2 unholy Death Knights in a raid.

Scourge Strike - 1 talent
A strike that deals 60% weapon damage as shadow damage plus 190.5, and an additional 95.25 bonus damage per disease. Costs 1 Frost and 1 Unholy Rune.
This is the bread and butter for an Unholy Death Knight. 25-30% of your total damage will come from this ability which (depending on your haste) can be more than your auto attack damage. It hits very hard and ignores armor since it is shadow damage. For the same reason it is also increased in damage by Ebon Plaguebringer.

Rage of Rivendare - 5 talents
Your spells and abilities deal 2/4/6/8/10% more damage to targets infected with Blood Plague. Also increases your expertise by 1/2/3/4/5.
This talent affects all your damage except auto attacks, which means 75% of your damage. So these 5 talents grant you 7.5% damage increase as well as 5 expertise. The 5 expertise makes it considerably easier to reach the expertise cap of 26 on which 60% of your damage depends (Scourge Strike, auto attack, Blood Strike and Plague Strike). 5 expertise equals 41 expertise rating. This talent should be maxed.

Unholy Blight - 1 talent
Deals 48 (+ 0.01 * AP) shadow damage every second to enemies within 10 yards. Lasts 20 seconds. Costs 40 Runic Power.
It doesn't sound like a whole lot of damage and some would argue that Death Coil is a better use of your Runic Power. But raid buffed Unholy Blight will tick for 220ish which means that the ability deals 4400 damage for 40 Runic Power. That is the same cost as a Death Coil, but Death Coil's average damage is more in the region of 3-3.5k. So even if you cut some ticks on Unholy Blight when renewing it, you will still deal more damage with Unholy Blight. Let's assume 3.5k average damage on Death Coil. Then Unholy Blight becomes better after 16 ticks. The ability becomes even stronger in AoE situations obviously.

Blood

You will find yourself spending at least 51 talents in the Unholy tree so here is a discussion of the top part of the Blood tree which is the optimal 2nd tree to spend points in.

Butchery - 2 talents
Whenever you kill an enemy that grants xp or honor you generate up to 10/20 Runic Power. In addition you generate 1/2 Runic Power every 5 seconds while in combat.
Granted, this is not the best ability ever, though the free Runic Power generation is nice. The reason you take the talent is to be able to reach the next tier of Blood talents, and the alternative is 4% parry which is useless.

Subversion - 3 talents
Increases the critical strike chance of your Blood Strike, Heart Strike and Obliterate by 3/6/9% and reduces the threat generated while in Blood or Unholy Pressence by 8/16/25%.
This talent is taken due to the 25% threat reduction which allows you to basically never worry about getting agro in single target fights, which may allow you to put out more damage. The 9% crit chance on Blood Strike is nothing, considering Blood Strike is less than 4% of your total damage.

Bladed Armor - 5 talents
Increases your Attack Power by 1/2/3/4/5 for every 180 armor value you have.
Before you get your hopes up too much, this does only apply to armor from items, not bonus armor from being in Frost Pressence. It is still a very nice talent. At ilvl 200 (naxx 10man and heroics) level you will find yourself with around 13k armor from items, which is is 360 Attack Power from this talent = 72 AP / talent.

Scent of Blood - 3 talents
You have a 15% chance when being struck by a ranged or melee hit to gain the Scent of Blood effect, causing your next 1/2/3 melee hits to generate 5 Runic Power. Can't occur more often than once every 20 seconds.
Useless talent as it only procs on direct attacks which means that you either have to be cleaved (bad positioning then) or pull agro to get anything out of this talent. No point wasting points in this talent with 2 great alternatives in the same tier.

Two-Handed Weapon Specialization - 2 talents
Increases the damage you deal with two-handed melee weapons by 2/4%.
This talent only affects your melee attacks (around 60% of your total damage), but it is still a 2.4% damage increase, or 1.2% per talent. Definately worth taking.

Rune Tap - 1 talent
Converts 1 Blood Rune into 10% of your maximum health. 1 min cooldown. Costs 1 Blood Rune.
This ability can be rather useful in situations with high incoming damage, but if you take the talent you must glyph for it to be really useful. Being able to instantly heal yourself (as well as your party with glyph) on a 1 min cooldown is not bad. In most encounters though, it should not be needed and you can safely go for 1% crit instead (Dark Conviction, see below). It's a matter of preferences though and math can't help you decide as the 2 abilities are so different in nature.

Dark Conviction - 5 talents
increases your critical strike chance with weapons, spells and abilities by 1/2/3/4/5%.
This is a very standard talent then almost all classes have, but it is nonetheless a good talent. Increased crit chance is always a nice damage boost, especially when your main ability (Scourge Strike) crits for an additional 45% damage. How many points you take in this talent depends on whether or not you go for Rune Tap and/or Improved Rune Tap.

Improved Rune Tap - 3 talents
Increases the health provided by Rune Tap by 33/66/100% and reduces its cooldown by 10/20/30 seconds.
If you decide to go for Rune Tap it is definately not a bad idea to take this talent too. 10% health is not much, but with glyph and this talent you can heal yourself for 30% and your party for 10% on a 30 seconds cooldown. Very nice help in AoE heavy encounters, but it is rarely a must to have.

Spell Deflection - 3 talents
You have a chance equal to your parry chance to take 10/20/30% less damage from a direct damage spell.
The keyword here is DIRECT damage spell which means that you have to pull agro to get any bonus from this talent, and even if you do you have a very low parry chance so the talents are pretty much wasted here.

Frost

Frost only offers 2 talents that one could consider taking as the rest in the top of Frost only boosts your Icy Touch (and possibly your Frost Fever).

Toughness
Increases your armor value from items by 3/6/9/12/15% and reduces the duration of movement slowing effects by 6/12/18/24/30%.
The reason one would consider this talent is its synergy with Bladed Armor in the Blood tree. Toughness increases your armor which in return increases your Attack Power through Bladed Armor. It just happens to be that the actual AP you get from this is very low. If we again assume 13k armor from items, you get 50 AP from this talent. And this is at the cost of 5% crit from Dark Conviction. This is clearly not worth taking.

Annihilation
Increases the critical strike chance of your melee special abilities by 1/2/3%. In addition, there is a 33/66/100% chance that your Obliterate will do its damage without consuming diseases.
Since you never ever use your Obliterate spell, this talent would only be used for the 3% crit chance. As such, it is a fine talent, but the fact that it requires you to spend 13 talent points to get makes it a very poor investment.

Glyphs

There aren't that many viable glyphs at the moment, but you have the following to choose from. In the spec section I will mention which specs should choose which glyphs.

Major:

Glyph of Scourge Strike
Your Scourge Strike has a 25% chance to refresh the duration of your Blood Plague and Frost Fever.
It sounds unreliable and it is to some degree but if you look abit ahead when you play, you can easily gain alot from this glyph. As long as you got your diseases up you wil be doing 5 SS in a row which means that you got a 76.3% chance to renew your diseases. This means that you can easily get 1 minute+ streaks where you only cast SS and BS, which is massive damage. An excellent glyph.

Glyph of the Ghoul
Your Ghoul recieves an additional 40% of your stamina and strength.
This glyph is a nice boost for your pet, both survivability and damage. 40% additional strength is around 400 unbuffed. Sadly the Ghoul only has a 1:1 conversion on str:AP but it's still 400 AP which is quite a bit. Should be taken by any spec that has perma-pet.

Glyph of Icy Touch
Your Icy Touch generates an additional 10 Runic Power.
The 2 above mentioned are given, but the last major glyph is less obvious, and depends on your spec. You don't use IT all that often (let's say once every 30 seconds) which is 1 Runic Power / 3 seconds. This is like an extra point in Butchery. It's not a whole lot, but it gives you extra ranged utility on bosses where you can't melee at times, such as Heigan or Malygos during Vortex. Without the glyph you can do the following: IT, IT, BB, BB, DC, wait, IT, IT (have 20 runic power left). With the glyph you can do: IT, IT, BB, BB, DC, wait, IT, IT, DC (0 runic power left). This means that you get a free Death Coil when ranged dpsing.
The glyph also makes it easier for you to keep up gargoyle as you can fire some ITs if you are getting low on Runic Power prematurely.

Glyph of Plague Strike
Your Plague Strike damage is increased by 20%.
Unless you spec for Outbreak and Desecration, this is the worst of the 3 glyphs. Plague Strike's total damage is lower than Blood Strike and even if you don't want Icy Touch glyph, Blood Strike glyph is better. So only take this glyph if you rely alot on Plague Strike.

Glyph of Blood Strike
Your Blood Strike deals an additional 20% damage against snared targets.
Although bosses can't be slowed, they will still count as being snared when being hit by abilities such as Infected Wounds or Thunderclap, which means that bosses are pretty much always considered snared. Blood Strike hits harder and more often than Plague Strike so is to be preferred above Plague Strike glyph. Whether you take this or Icy Touch is a matter of personal preference.
As a bonus info, Blood Strike glyph also affects your Heart Strike, should you spec into Blood.

Glyph of Rune Tap
Your Rune Tap ability also heals your party of 10% of their maximum health.
Although the effect of this glyph is not increasedd by Improved Rune Tap (the glyph still only heals for 10% on party), it is still a must-have glyph if you spec for Rune Tap. The glyph does not heal yourself for an additional 10%, only your party members.

Minor:

Glyph of Pestilence
Increases the radius of your Pestilence effect by 5 yards.
This means that it becomes easier to spread your diseases as Pestilence now hits everyone within 15 yards, instead of 10 yards. Very nice talent as you don't have to think about your positioning when casting Pestilence.

Glyph of Horn of Winter
Increases the duration of your Horn of Winter effect by 1 minute.
This is a so so glyph. If you run a rotation where you can't fit in HoW without losing damage, it is a good glyph, but in most rotations you can easily fit in Horn of Winter in your rotation (with benefits), which means that you don't need to increase its duration by 1 min. Additionally, taking this glyph means that people without the glyph can't use their Horn of Winter as long as there is 2+ mins left on the duration. This may be a slight nerf for their damage depending on spec and rotation.

Glyph of Raise Dead
Your Raise Dead spell no longer requires a reagent.
Personally I like this glyph as you never have to worry about bringing enough reagents and you should have no seconds thoughts about instantly ressing your pet in any situation. If you don't mind bringing lots of reagents and using them and you think you can get something better in another glyph, then skip this. But there's not a whole lot to benefit from the other minor glyphs.

Glyph of Corpse Explosion
Any target killed by your Corpse Explosion ability will also explode. Only affects targets within range of youor Corpse Explosion ability, and cannot happen more than once every 6 seconds.
This is a very nice glyph when AoEing. If there are mobs that die relatively easy, your Corpse Explosion is quite likely to kill them which in return will make them explode too, giving your Corpse Explosion double damage. Should be taken if you have Corpse Explosion.

Glyph of Death Embrace
Whenever your Death Coil is used to heal, you regain 20 Runic Power.
If you find yourself healing your pet alot, this glyph is very nice. But with Night of the Dead, Glyph of the Ghoul and the general AoE healing in raids (Judgement of Light, Blood Aura etc), you will most likely rarely be doing so, leaving this glyph unused.


Optimal Specs

In this section i will discuss how to combine your talent points into a strong spec.

The optimal spec when wielding a twohander and playing Unholy is 17/0/54. As shown in the talent section the Frost tree does not provide any easily accessible buffs to your abilities and you should therefore not spend any points in that tree. There are a couple of variants of this build and i will discuss which one to choose:

The Traditional:
This is the most used spec in high end raiding and the spec that has been proved to be strongest. You skip a talent point in Blood-Caked Blade in order to be able to max Virulence. If you want more AoE power (although the spec is already incredibly strong in AoE) you can skip another point in BCB and take Corpse Explosion.
This spec lets you bring both Unholy Aura and Ebon Plague to the raid and you will deal alot of damage. All talents (except Unholy Aura) are focused on maximum damage. If you do not want to bring Unholy Aura of if someone already brings it, you can move those points to BCB and Corpse Explosion or Outbreak or Desecration. None of these choices should affect your rotation though, nor give any really noticable dps improvement.

The rotation with this spec is as follows:
No Scourge Strike glyph: PS, IT, BS, BS, SS, runic power dump -> SS, SS, SS, dump -> repeat from start
With glyph: PS, IT, BS, BS, SS, dump -> SS, SS, SS, dump -> at this point it depends on your glyph procs. As long as your glyph renews your diseases your rotation is BS, BS, SS, SS, dump -> SS, SS, SS. When you diseases are about to fall off and you only have 1 unholy and 1 frost left (or the diseases have fallen off already) you renew them manually with PS and IT. If they are about to fall off and you got 2 Unholy and 2 Frost (or Death runes) you should try with a SS first to see if it renews the diseases before manually renewing them.

The rotation can also be formulated as a Priority System as follows:
1) Death Coil if Runic Power is capping
2) Renew Diseases if they are falling off
3) Scourge Strike if possible
4) Blood Strike
5) Death Coil

Glyphs:
Major:
Scourge Strike
Ghoul
Icy Touch

Minor:
Pestilence
Ghoul (no reagent)
Horn of Winter (or Corpse Explosion if chosen)

The Survivalist:
This spec is simply a variant of The traditional spec, where you skip 3% crit in favor of Rune Tap and 2 points in Improved Rune Tap. Other than that it is exactly the same as above.
You might consider this spec if your healers are struggling keeping people alive on heavy AoE, but in most situations The traditional is to be prefered.

Glyphs:
Major:
Scourge Strike
Ghoul
Rune Tap

Minor:
Pestilence
Ghoul (no reagent)
Horn of Winter (or Corpse Explosion if chosen)

The Plague Striker:
This spec is build around keeping up Desecration and getting some decent damage on Plague Strike. This means that you skip Epidemic, which means that you will be using Plague Strike in every rotation. You lose Blood-Caked Blade, Unholy Aura and Night of the Dead though, which is a nasty hit to your pet's survivability as well as raid mobility. The spec has multiple times been proved to be inferior to The Traditional spec though and is not really worth considering.

The rotation is as follows:
PS, IT, BS, BS, SS, dump -> PS, IT, SS, SS, dump -> repeat all

Glyphs:
Major:
Plague Strike
Ghoul
Icy Touch

Minor:
Pestilence
Ghoul (no reagent)
Horn of Winter (or Corpse Explosion if chosen)


Runic Power dumps

If you ever find yourself capping your Runic Power you should fire a Death Coil, even if it is in the middle of a rotation. Wasted Runic Power is wated damage and is way more valuable than the slight delay on your runes.
There's a nice mechanic regarding Runes to know of when dumping Runic Power. As everyone should know, runes activate 10 seconds after being used. There is a slight tweak on this though. When a rune activates you have a 2.5 seconds interval where you can use the rune without causing it to activate later next time. Example: your first Unholy and Frost Runes activates at 00:00:00, but you're busy dumping Runic Power. If you choose to use the 2 runes right away they will go on cooldown and activate again at 00:10:00, but if you decide to cast another Death Coil to avoid capping your Runic Power, you will use the 2 Runes at 00:01:50 instead. The runes will still activate at 00:10.00 and not 00:11:50 as you would might think. This means that you can dump your Runic Power without having to worry too much about pushing your rotation and possibly losing overall dps. Should you chooce to wait till 00:03:00 before using the runes they will activate at 00:13:00 though, so don't push it too far.

Gear selection

When seeing new gear it is not always easy to judge which stat distributions are better. One solution is to use spreadsheets to check this, but at the moment there is a lack of accurate, user friendly Death Knight spreadsheets. So an alternative is to try to value the stats manually. This can be done by following this table, created by theory crafters at ElitistJerks.com:



These values are before melee hit cap. After melee hit cap (before spell hit cap) the values are :
1Hit 0.9167 0.9460 1.1139

Here's an example of all the epic weapons pre-Ulduar, sorted after ranking:
Demise : 1456.17 (assuming spell hit cap)
Wraith Spear : 1474.70
Titansteel Destroyer : 1486.20 (assuming spell hit cap)
Demise : 1497.42 (assuming hit cap, not spell hit cap)
Colossal Skull-Clad Cleaver : 1500.15
Claymore of Ancient Power : 1501.74
Titansteel Destroyer : 1535.71 (assuming melee hit cap, not spell hit cap)
Black Ice : 1543.84 (assuming spell hit cap)
Demise : 1567.01 (assuming full effect of the hit rating)
The Jawbone : 1596.93 (assuming expertise cap)
Black Ice : 1609.84 (assuming melee hit cap, not spell hit cap)
Titansteel Destroyer : 1619.21 (assuming full effect of hit rating)
Death's Bite : 1629,57 (assuming spell hit cap)
Cryptfiend's Bite : 1633.44
Armageddon : 1657.37
Death's Bite : 1686,40 (assuming melee hit cap and not spell hit cap)
Black Ice : 1721.18 (assuming full effect of the hit rating)
The Jawbone : 1724.72 (assuming full effect of the expertise rating)
Betrayer of Humanity : 1757.30
Inevitable Defeat : 1769.37 (assuming full effect of the expertise rating)
Death's Bite : 1782.28 (assuming full effect of the hit rating)


After 3.1 your pets (ghoul + gargoyle) will also recieve bonus from your haste (and possibly armor pen rating). The following table displays the values of stats in 3.1 for an unholy DK (14/0/57):



Gems

For a meta gem you will want Chaotic Skyflare Diamond. This meta gem requires you to use at least 2 blue gems. For blue gems your best choice is Sovereign Twiligt Opal (8 str/12 sta) and your second best choice would be Guardian's Twiligt Opal (8 exp/12 sta) if you aren't expertise capped. After you have achieved the meta bonus you should consider consider 1 of 2 options for the rest of the gems. Either gem with Bold Scarlet Ruby (16 str) in all slots or use a combination of colors if the socket bonus will get you a higher total score (refer to the above table). The gems to choose for the given colors are:

Blue: Sovereign Twiligt Opal (8 str/12 sta)
Yellow: Etched Monarch Topaz (8 str/8 hit) if not hit capped. Otherwise Inscribed Monarch Topaz (8 str/8 crit)
Red: Bold Scarlet Ruby (16 str)


Enchants

The preferred enchants for each slot are as follows:

Head: Arcanum of Torment (50 AP / 20 crit)
Shoulders: Greater Inscription of the Axe (40 AP / 15 crit)
Cloak: Major Agility (22 agi)
Chest: Powerful Stats (10 to all stats)
Bracers: Greater Assault (50 AP)
Gloves: Precision (20 hit, if not melee hit capped) or Crusher (44 AP)
Legs: Icescale Leg Armor (75 AP / 22 crit)
Boots: Icewalker (12hit / 12 crit, if not melee hit capped) or Greater Assault (32 AP)
Weapon: Rune of the Fallen Crusader (proc: heal for 3%, increase str by 30% for 15 secs)


Consumables

When raiding you should always be fully buffed with consumables. In all situations flasks are better for Death Knights, but if you flask run out 30 mins before a raid ends you can choose to use Elixirs for the rest of the night without too much loss. The preferred consumables of each type are:

Flask: Flask of Endless Rage (180 AP)
Battle Elixir: Elixir of Mighty Strength (50 str)
Guardian Elixir: Elixir of Mighty Fortitude (350 hp, 20 hp5)

Food: Dragonfin Filet (40 str / 40 sta) or Worg Tartare (40 hit / 40 sta, if not melee hit capped).
If you are hit capped and don't have access to Dragon Filets you can use Mega Mammoth Meal (80 AP / 40 sta) or Rhinolicious Wyrmsteak (40 exp / 40 sta).



Feel free to start discussions based on this

Beautiful guide mate, really nice breakdown on the skills used and talent build.

Just wondering if your table of values has the 3.1 weightings for ArP and haste or will you wait for release to reconsider these? Think ArP gets a 25% boost and haste 30% for melee speed.


Slight correction on Glyph of Bloodstrike - Frostbolt and FFB dont count as snares on boss fights, only attack speed slows that they are not immune to count (Same as Torment of the Weak: Arcane talent). Infected wounds, thunderclap etc count as snared so tanks keeping it applied is important, think there are a few others like Razorice?.

EDIT: FFB may count as snare as it applies a piddly little dot, cant remember as I havent specced it in ages.

The haste and ArP values in the 3.1 table are including the boost they get. The ArP is without its contribution to pets though as it's not quite clear yet how much they get (from the info ive been able to find).

Corrected the FFB thing, thx