I've been trying to figure out the optimal way to gear my 2h Frost DK (I tried DW and it seems worse), but I've found so much misinformation online that I decided to do some in-depth research and testing. I will outline what I found here, and the conclusions I am drawing. Check it out and let me know if I missed something, or tested something incorrectly. I will keep this updated with corrections as much as I can. Thanks for reading!

**TLDR**: See my stat priority and gear suggestion at the bottom.

**Change History:**

Jan 13, 2015 - Haste rating effect buffed by 11.1%, Icy Talons buffed to 20% haste, up from 5%. Note that tooltips in the game are not updated yet (possibly requires a client patch), but I can confirm the changes are live due to seeing them on my stat sheet. See edits in green throughout the post.

**Special Notes:**

(*) means I assume it's correct if not bugged but I didn't test it. I'll put this next to things I take for granted.

(**) means I actually tested this to prove that it is indeed this way. For brevity, I didn't outline how, but I can if requested.

(?) means I'm not sure, but if someone could test this somehow, it would be great

Let's start with seconday stat ratings and how much damage they contribute.

**Rating points required for 1% increase (** tested this myself):**

Haste

Crit 110

Multistrike(MS) 66

Mastery(MA) 55

Versatility(Vers) 130

Let's take a realistic but nice looking number of how much of each stat you could stack, say 1000 rating points.

**For 1000 rating points you would get:**

9.09% Crit

15.15% MS

18.18% MA

7.69% Vers

In addition, stats scale linearly. So adding 11.1% Haste when you have 40% has the same impact as adding it when you have 0%, assuming you don't hit a cap.

**NOTE:**Crit and MS are nerfed in PvP! This may be obvious to some, but a lot of people don't take this into account when calculating stat priorities! Each Crit does 150% damage instead of 200%, and there is only one chance at a 30% MS instead of two chances. This also applies to heals!

Taking the nerfs into account, let's do an average damage increase you would get from each stat if you stacked 1000 rating worth. I will not account for burstiness here, because getting a string of lucky crits of multistrikes can always happen, but it will even out in the end, and you don't want to rely on pure luck to win arena matches.

**Haste (**~~10.91%~~ 13.86% (given infinite uptime) DPS increase per 1000 rating points):

Haste is really good, and was recently buffed. Here's why.

EDIT: Since Icy Talons(10% and 20%) and Unholy Aura(5%) apply multiplicatively,

**all haste you equip is getting multiplied by 1.1*1.20*1.05 = 1.386.**

Let's take an example:

I have 15.50% base haste with nothing equipped. Icy Talons gives 10% flat, plus an additional 10% modifier on every other haste effect except Unholy Aura for some reason. Unholy Aura gives 5% flat, plus an additional 5% modifier on every other haste effect. This gives 10 (icy talons) + 5 (unholy aura) + 10*0.05 (unholy aura bonus to icy talons base 10%) = 15.50. I am an NE so I get 1% Haste at night, but I did this test during the day where I did not have that 1% buff to Haste. I also did the test at night and the numbers I see are consistent.

Icy Talons (recently buffed) also adds 20% more of the equipped haste stat.

When you add Unholy presence on top, it adds yet another factor, multiplying (not adding to) every source of haste by another 10 or 20% (depending on spec), as well as adding its own 10 or 20% base amount.

1000 Haste rating / 90 pts per % rating * 1.386% extra for Frost DKs = 15.4% Haste, but let's use 15% for the sake of example since it's a nicer number.

- 15% haste means 15% faster attack speed, which means 15% more auto-attack damage (**).
- 15% haste also means 15% more Killing Machine (KM) procs (**) due to increased attack speed.
- 15% haste also means 15% faster rune regeneration (**), meaning that (for ex) over 100 seconds, a rune would fully cycle 11.5 times instead of 10 if you depleted it instantly every time it came back.
- Haste does NOT affect the GCD because it's already capped at 1 second (**).
- Haste does NOT affect any of our diseases (**).
- Haste does NOT affect Conversion, or Breath of Sindragosa (BoS), or any skill that says it ticks "every X seconds".

- Haste does not fully kick in immediately once you start attacking. At first you will get faster auto-attacks, so about 2.6-3 seconds after you attack, you will get a second auto-attack that will be sooner with more haste. But after that, it will take around 7 seconds for runes to start coming back due to higher haste. This is improved by Runic Corruption, which seems to have a nice smoothing effect on rune availability at high haste. In my tests I find that I wait 1-2 seconds less for an Oblit to become available after unloading RP when using 14% haste. Blood Tap will have an even stronger bursting effect due to on-demand Death Runes, but Runic Corruption can proc repeatedly and tends to give smoother rune availability with less waiting in general. This is great if you run Breath of Sindragosa.
- Haste does not affect diseases. From my tests, diseases seem to compose at most 10% of my DPS. (?) Needs more testing.
- Haste does not affect the GCD.
- Haste does not affect Breath of Sindragosa while it's up, so it will not make it burst faster. However, it will make your runes come back faster, which might allow BoS to stay up longer (?) due to the extra runic power you will have.
- Haste can at most affect the recharge of 3 runes simultaneously. If you don't have one rune of each type depleted, then Haste's contribution is being reduced. If you have 2 runes recharging, then you're getting 66.7% of Haste's effect. One rune is 33.3% etc.
- Haste is uptime dependent. (EDIT: See the blue text below for uptime explanation) This means that if you can't keep one of each rune type constantly on cooldown, then you won't get all of its DPS increase.
~~Haste also has a bit of defensive utility because it gives you more runes to Death Strike when in trouble. I personally find that I have very good uptime running PHD and in RBGs, so maybe some comps benefit more from it as well. If you find yourself sitting on two unused runes of the same type, then haste is not the best for you. You should go with Versatility instead (see below)~~Due to the recent Haste buff, it's even harder to not get more overall DPS out of Haste than Versatility.**You now need to be sitting on 2 pairs of unused runes in order for Vers to be higher DPS.**Vers will still offer higher burst though. - Haste also adds some utility because you will be able to use Icy Touch more often for purges, plus more uses of Chains of Ice, and you will have more RP for interrupts, Conversion, and Dark Simulacrum.
- I also see a lot of people saying that if you have a crappy connection, Haste is worse. This may be real if you lose some time after runes come off cooldown. Try switching to Unholy presence and feel the effects of 10% more haste. Imagine that effect in Frost presence where you don't lose the RP gen, and see if it would be better for you.
- There is concern that there's such thing as too much haste because past a certain point network lag and uptime start really hurting. I am currently sitting at 35% Haste (15% from gear) and I feel like I could use even more. You can't get much past 19% from gear with the current gear available, so I don't think it will become an issue this season. For those wondering, I did some calculations, and you would need to stack 2240 Haste as Frost in order to hit the cap. By my count, the most you can reach right now with the current gear is 1396, so we are far from the cap. I was previously wrong in thinking that Unholy Presence will make you hit the cap. It doesn't. I'm at 51% in unholy presence right now. I think only the base haste is capped at 50%.

**Crit (3.64% DPS increase per 1000 rating points):**

Yes, Crit is really bad, and probably the worst stat for Frost. Here's why.

1000 rating / 110 rating per % = 9.09 Crit chance for 1000 rating.

So we are adding a 9.09% chance to do 50% additional damage, meaning on every attack that can crit we are adding 4.545% damage.

- Diseases can Crit! Actually all damage a DK does can Crit! (*)
- But there's a catch: Killing Machine. KM guaranteed Crits means the your Crit is useless when KM procs! Based on my tests, about half of my obliterates or more are used when KM is up. If you are really good at managing your runes, it might be more than half, but let's assume half for now. On my tests, my obliterates do between 40-50% of my overall damage no matter if I'm bursting, or just normally DPSing. So that means that if half my oblierates don't use KM, then my Crit is not being used half the time on my Oblits, so the real Crit contribution is more around 4.545% * 80% = 3.64%.

**Multistrike (4.545% DPS increase per 1000 rating points):**

As Blizzard themselves have said, Crit and MS are equal, even in PvP.

1000 rating / 66 rating per % = 15.15% MS chance for 1000 rating.

So we are adding an 15.15% chance to do 30% additional damage, so by simple math: 15.15% * 30% = 4.545% damage increase.

- Every attack can MS, including diseases. I am not sure if Death Strike healing can MS (?), but I am pretty sure that Conversion cannot (?).
- Multistrikes can crit! And KM procs (if they proc MS), will automatically Crit on the MS proc.
- I see some sites saying MS is the best stat, but I just don't see it in the math; far from it in fact. Maybe they are forgetting it only procs once in PvP? Maybe I missed something?

**Mastery (~6% DPS increase per 1000 rating points):**

This one is a bit fuzzy because it highly depends on how much Frost is contributing.

1000 rating / 55 rating per % = 18.18% Mastery for 1000 rating.

- This means 18% increased Frost and Shadowfrost damage (**). But how much of our damage is actually Frost or Shadowfrost?
- According to my tests, I get between 25-40% Frost damage (when doing regular dps), averaging around 33%. Strangely enough, this applies even when doing crazy burst with BoS, because you are not using Frost Strike.
- So therefore 18.18% * 33% = ~6% damage increase per 1000 Mastery. This beats Crit and MS assuming at least 25% of your damage is Frost or Shadowfrost, which is a pretty safe assumption.
- I'd like to see more discussion on Mastery because I'm not sure where it will sit in the priorities.

**Versatility (7.69% DPS increase per 1000 rating points):**

This is the easiest one to calculate. This is a great stat because it offers healing and defense bonuses.

1000 rating / 130 rating per % = 7.69% Versatility for 1000 rating.

- 7.69% Versatility means 7.69% more damage across the board on all damage DKs do (*).
- 7.69% Versatility means 7.69% more healing on Deathstrike, and other heals that are not %life based. Versatility does not increase Conversion healing!(**) Death Pact (?)
- 7.69% Versatility also means 3.85% less damage taken from all sources (*).

**Some ugly facts I found while testing:**

- The 4pc Frost DK PvP set bonus does not work on Shadowfrost damage. BoS and Necrotic Plague do the same damage regardless of you activating the 4pc bonus (I didn't test reaper since target dummy can't go below 35% hp). This is probably a bug, and I have reported it. I was doing 2v2 with a Frost Mage and was running it, but I'm not sure if the Frost Mage is getting any benefit (?).
- The PvP target dummy at the Glad Sanctum takes double damage from crits instead of 50% more - probably a bug. Multistrikes are also causing 2 strikes instead of 1.

**Strength:**

I didn't test anything for Strength, but it almost never overlaps with secondary stats, so not much to discuss here. Even if it does, Str gets so many insane %-based bonuses from DK passives and procs that it easily outdoes the other stats (*).

**Putting it all together:**

- All the numbers are for 1000 rating in isolation. Some may wonder if it changes when you throw all the stats together and in different amounts. I would say that in most cases it does not because stats do not interact in any way that provides a faster or slower damage increase than each stat would on its own.
- Strengh is most likely the best stat in all cases, unless someone can prove otherwise.
- Haste and Versatility are both really good. Haste is better in terms of pure math, but Vers benefits your early burst more (i.e. the first 7-8 seconds of DPS after starting with full runes). We are looking at 13.86% more DPS (but not in the first few seconds of damage) vs 7.69% more DPS (active at all times). Haste's benefits will only fully start showing up after runes start coming off cooldown. During the initial burst, you will only gain the increased auto-attacks and KM procs. Versatility does have the healing and damage reduction benefits, though they are less important for DKs compared to the damage benefit, and Haste has some built-in survivability too due to the rune regen for Death Strike, and extra RP for Conversion. This could make a great discussion to see which is better, Haste or Vers. Looking at the DK gear though, it looks like you can usually get them both together. If your connection sucks, or you think that Haste feels worse when you play, go for Vers since it is by far the best other choice.
- EDIT: I have been studying the uptime requirements of Haste and here's what I see: you are getting 100% of Haste's effect if you constantly have at least one rune of each type on cooldown. That is, you must have at least 1 death rune, 1 frost rune, and 1 unholy rune on cooldown. Haste also increases autoattack speed, but most of the benefit is in the runes, not the autoattack. It's probably common knowledge that only one rune of each type can be recharging at a time (if not, see Haste section above).
**Haste DPS is only worse than Versatility if you are sitting on**I have been checking my runes for a few weeks now, and I am almost never sitting on two rune pairs while in combat (except at the beginning when all runes are up, but it takes only 1 GCD to put enough runes on cooldown). Even if you're kited, you are still using icy touch for purges (thanks Scoot), chains of ice, howling blast, etc and using up those runes.~~two runes of the same type~~two rune pairs for a significant period of time. - There is no doubt that Vers is better for bursting. Haste doesn't help you much if you're blowing ERW and Plague Leech.
- From my own experience playing with various levels of Haste and Vers, I think the magic number for Haste is 33%. At 33% I feel that I get the smoothest rune availability. However, you have to give up some Vers to get 33% Haste because with my recommended gear set below you will only reach 30.4% Haste. 33% vs 30.4% is actually noticeable for me, so it's really tough deciding if I want that rune smoothness versus the extra burst, but in the end I have decided to go with burst.
- Crit is flat out the worst from the numbers.
- MS and Mastery are an interesting discussion. Mastery seems to be better if you can have more than 25% of your damage as Frost or Shadowfrost, but MS can be more bursty. I tend toward MS because I like seeing numbers, and because Mastery seems really boring, but gearing into Mastery might serve you well if you also play Unholy.

**Stat Priority:**

So the stat prio in my opinion (and after much experimenting) is the following ('>>' means much better). Although Haste offers higher long-term DPS, Vers is better for bursting and for surviving damage dealt to you in 3v3. Because of this, Vers should be the way to go.

**Str >> Vers >**

**Haste**

**> MA >= MS >> Crit**

**Gear Selection:**

Here is my best attempt at putting together a gearset that satisfies the above. I would take the 2pc set bonus (since you gain very little by dropping it, and it's actually pretty good), but not the 4pc. I will adjust this based on any new data though.

**NOTE**: Some Vers pieces require Revered with the Ashran faction. This might seem annoying, but it's actually extremely easy. Go to Ashran, but don't group into a raid. Run solo, and loot as many enemy corpses as possible. Occasionally you will get a blue item that you can hand in at your home base for 2750 rep. I got to revered in 1 hour doing this.

Helm: MS/Vers

Chest: MA/Vers

Shoulders: MS/MA Set piece shoulders. The MS/Haste shoulders are better, but need the 2pc bonus.

Gloves: Vers/Haste

Legs: MA/Haste Set piece pants.

Boots: Vers/Haste

Belt: Vers/MA

Bracer: MA/Haste

Neck: MS/Haste

Cloak: MA/Haste

Ring1: MS/Haste

Ring2: MA/Crit (or take MS/Crit if you like MS more. Very minor difference.)

Trinket1: Vers with proc Str

Trinket2: Str with on use Vers

Enchants: Vers (you can change some of them to Haste if you feel you're too rune-starved)

Final projected bonuses:

+10.3% MS (11.8% if you took the MS ring over MA)

+18.5% MA (16.7% if you took the MS ring over MA)

+9.0% Vers

+2.8% Crit

+14.9% Haste