I've gotten more data to run tests on while I'm on flight. I'll let you guys know in a bit. I think they may have tried to somewhat haphazardly fix ArP or use level-based suppression as dysent mentioned.

Armor reduction is a value depending on the attacker, so it makes sense that A is half armor value for a lvl 80.
There are many reasons why it can be different vs lower level targets, but we need progressive tests from a lvl 75 to 80 attacker versus a lvl 75 to 83 defender. This could lead to some appropriate result.
Anyway it can easily be a particular factor for boss targets, like crit depression, and maybe the .81 value of arp can depend on that too. we should see if it scales with different levels.

Unfortunately target dummies are only either level 70, 80 or 83. The ideal targets would be 75 to 83 with a 1 level increment.
While could be easy to find beast mobs (a hunter can precisely measure their armor) between 75 and 80, it won't be so easy to test 81 and 82 targets outside instances.

Alright, here's what I got from some testing earlier today that I've been mulling around in my head:

Here's what I got vs Heroic dummy, which perfectly fits the model.

Gear	zerk	battle	zerk+5S	battle+5S	ArP	BT
set 1	726	751	789	818	0	1234
set 2	1072	1112	1194	1247	90	1534
set 2+GT	1216	1267	984	1020	702	1534
set 3	1009	1045	1115	1163	218	1573
set 3 + GT	1301	1359	925	958	830	1573

Here's what I got from a lev 80 dummy, which the model doesn't match. By manipulating A, I can make the 0 ArP items line up, but then whenever ArP is introduced, the numbers are wrong.
What I got when I tweaked a bit was B~= 9710, x[L80]~=.8535x

gear	zerk	battle	zerk+5S	battle+5S	ArP#	Base BT
set 1	753	779	817	845	0	1234
set 2	960	994	1041	1077	90	1534
set 2+GT	1156	1205	1254	1307	702	1534
set 3	1020	1057	1106	1146	218	1573
set3 + GT	1238	1294	1342	1402	830	1573

This means that the level 80 dummy values need to be explained using a different correction factor for x than the level 83 dummy values.

Which raises an interesting question of why in the world the correction factor would be different... and throws a great big monkey wrench in the whole "ArP is bugged by 19%" thing...

I'll try testing vs beasts like Hellord said - and also against players as I have time. Anyone else who can provide testing results, I would greatly appreciate it.
Also: test at 0-31-0 if possible, not taking any talents that give a global % DIM to your abilities. This gives us as close to a "pure" test as we can get.

I went to the L83 Heroic dummy just now. I have 2419 AP (1209.5 base BT) and I keep hitting for 830 and critting for 1827. That is completely inconsistent with your hits for 726 on 1234 base BT and I have no idea why.

Edit: I was an idiot and forgot about the 10% bonus to BT from talents. That being said, 830 on base 1330.45 is still relatively inconsistent with 726 on 1234 base.

You're indicating the boss dummy has 62.4% armor reduction. Multiple testing has shown it has 58.87% reduction.
http://elitistjerks.com/f31/t29453-c...7/#post1180655 is the post where Rallik nailed it down to 10643 armor.

I suggest using a 0-31-0 spec without % changes to damage via talents. These multipliers have confused your data :\

---------
Talent issues aside, I'm testing at 0-31-0 vs the 80 dummy with the same equipment that gets me expected results on the 83. I presented the data set earlier, but here's some math to help see where my concerns are coming from:

First, let's examine the armor on the dummy. To get an exact value, I'll need to repeat Rallik's process, but we can get a range from my limited initial testing:

Math: 1234 BT base, 753 to 754 dmg observed
753/1234 = 61.0211% dmg remains. Solving A/(A+B) = 61.10211% for B gives us 9730.179
754/1234 = 61.1021% dmg remains. Solving A/(A+B) = 61.11021% for B gives us 9697.118
So the range of armor for L80 dummy is 9698 to 9730. I'll be using 9720 until we get an exact number, because my data tracks well against it and the difference is going to be fairly minute.

Now, let's examine some of the numbers I got, using B[80] = 9720:

gearset: 0 ArP, 1234 Base BT
Mdl1: using x[base] : what we think ArP "should" be
Mdl2: using x[LIVE] = x[base]*.81 : what ArP is vs an 83 dummy on live
Mdl3: using x[TEST] = x[base]*.8535 (trial and error value)
Observed values were 5 tests for each gearset for each sunder/stance. They're averaged

_______	_______	_______	_______	_______
info	zerk	battle	zerk+5S	battle+5S
observ	753.0	779.0	817.0	845.0
x[base]	753.31	783.84	816.95	850.07
x[LIVE]	753.31	777.85	816.95	843.57
x[TEST]	753.31	779.21	816.95	845.05

So... x[TEST] appears to be a more reliable predictor than x[LIVE], the current model vs the 83 dummy.

Using a bunch more ArP, we'll take a set with 218 ArP, 1573 BT

_______	_______	_______	_______	_______
info	zerk	battle	zerk+5S	battle+5S
observ	1019.6	1057.6	1106.0	1146.6
x[base]	1031.36	1076.40	1118.50	1167.35
x[LIVE]	1017.05	1052.22	1102.99	1141.12
x[TEST]	1020.30	1057.60	1106.75	1147.45

Now note that the predictor isn't perfect. x[TEST] was correct to +/- 1 damage, but it's still not exactly right. I couldn't find a value that improved the x[TEST] model for all values - it'd improve some and push others further off.
Any level scalar might not even be to x, it might be to x and y both, or to the entire result.

Here's a test with significantly more ArP, so more variance can be observed:
Set above + GT: 830 ArP (I didn't get 5 tests for all values here, so the averages are between 2-3 values. It became very time consuming waiting for GT procs and then getting 2 BT's in and praying for noncrit)

_______	_______	_______	_______	_______
info	zerk	battle	zerk+5S	battle+5S
observ	1238.0	1293.3	1342	1402
x[base]	1302.06	1374.67	1412.07	1490.81
x[LIVE]	1219.58	1270.49	1322.62	1377.83
x[TEST]	1237.32	1292.66	1343.51	1403.95

Note that we start to see more variance between the test model and observation at 830 ArP, but primarily when the target is also sundered. I tried both extremes of B and this variation is not explained by small variations of B within the range above.

Either way, that's my data and analysis for a ~ .8535 scalar (or a 14.65% penalty) vs level 80 targets. I've got it all on a spreadsheet, so if anyone wants a spreadsheet that will do repetitions of the various ArP formulas for test data, just msg me and I'll shoot you what I have.

Next step is coming up with a formula that works against many different enemy levels and armor values, and ensuring there's no differences based on fighting players instead of mobs or based on "boss" status or some other variable. For that, we need as much data, data, data as we can get from testing BT with a 0-31-0 spec against targets with known and varying armor values.

Went back and fixed modifiers in my Excel sheet. Data matches the expected on the L83 dummy.

What I intend to do when I get some time tonight is to conduct some more tests, specifically:

L80 dummy with multiple levels of ArP to get a sort of regression data for that.
L80 player with multiple levels of armor and ArP to get more data on that.
L81/82 mobs [both elite and non-elite to see if we get different results with that] with 0 ArP (to find their armor) and ArP equipped

Candidates:
Pustulent Horror - NPC - World of Warcraft
Plague Drenched Ghoul - NPC - World of Warcraft
Skeletal Minion - NPC - World of Warcraft

L70-79 Mobs with similar data needs (this should be easier as there are many, many more mobs like this)
L70-79 Players for similar data needs.

Perhaps we should coordinate data collection to minimize the amount of time it takes us?

ok so what is really better for PVE, is it arms not that titans grip got nerfed or is fury still better?

At the risk of getting an infraction for replying to this abortion of a post, I'll answer with my own experience since it seems to be a popular question. I tried both arms and fury with the same gear (I don't really have multiple sets) and while arms came out about 150-200 dps ahead on a target dummy, in an actual raid I found fury outdid my best arms attempts by 300-400 dps. I'd say the main reason(s) for this are gear and rotation.

An arms rotation is a lot more GCD intensive, and relies on being able to track rend, and keep your eyes open for what's procced or coming off CD. This can be very hectic in fights that require a lot of movement and/or target switching. If you really want to make arms work you'll need a DoT timer for rend, and power auras or a similar addon to keep track of TFB/SD/MS or what have you. For the majority of the population, staying fury and mashing BT/WW will probably produce more DPS in most cases.

I haven't tested extensively, but it would seem they broke shockwave in the patch - it would appear that if the target is immune to stuns, he's also immune to the damage portion. At least that's what I saw after a "few" tries on XT-002 Deconstructor. Concussion Blow seemed to work fine.

Filtered WWS log

Yep I got this too. I used Shockwave when tanking Kologarn and got 3 (arms and body) immune messages and no damage whatsoever.

Actually there are a lot of fights in Ulduar where you can utilize Warbringer and sweeping strikes as arms, which are huge heads up against fury. Vezax also has a -20% haste debuff which kills the Fury rotation. Yogg-Saron is a big frontload burst fight and the first two phases you are often attacking 2-3 mobs at once (can't say anything specific go find out for yourself). If you were a dps warrior for Ulduar, I'd totally recommend dual speccing into both and picking the spec that favors the fight or trash even. You can make the differring caps with like a ring or belt or bracer swap. Also, you might want to carry around extra cleave and execute glyphs (if you are rich) with you to switch out.

I definately think movement fights favor arms a lot more because of warbringer/charge/mortal strike. Fury rotation with the 10% nerf is really really tight and you have to be on target 100% of the time to get proper rage for a proper damage rotation. Arms you can just jump on something and spam whatever and guaranteed the rage for it all, and hit bladestorm in between MS, execute, and overpower, and rend refresh.

I think I posted this in the wrong spot earlier...

Since the 3.1.0 Patch I am trying to figure out what the heck I am supposed to do to respec in such a way to minimize the 10% penalty to damage for dual wielding 2H weapons. It seems like my strength is a lot more since the patch and my AP is great. Just looking for advice. I am currently spec 18/53/0 My current spec is as follows:

Fury Arms

Armored to the teeth 3 Improved Heroic Strike 3
booming voice 2 Deflection 4
cruelty 5 Iron Will 3
commanding presence 5 Impale 2
Dual Wield Spec 5 Deep Wounds 3
Precision 3 Two Handed Weap Spec 3
Death Wish 1
Improved Intercept 2
Improved Berserker Rage 1
Flurry 5
Blood Thirst 1
Intensify Rage 3
Improved WW 2
Improved Berserker Stance 5
Blood Surge 3
Rampage 1
Unending Fury 5
Titan grip 1

After looking at a couple of specs I noticed some choose to use the Improved Cleave. Is this the way to go or not? Thanks all. I appreciate the help.

I am also struggling with my rotation. Specifically i am being told that I should be doing tonnes more DPS than I am right now. My overall DPS in the last instance I ran was about 2101. I have mostly Epic gear now (from Heroics not Naxx). My AP is about 4500 buffed, crit is over 35% I think and str is like 1189. If I am doing it right.. what type of DPS should I be doing. Currently my rotation is as follows:

BR, Intercept, BS (if buffs from other party members are not better otherwise CS), DW, WW, BT (Slam if it procs) and then spamming HS until cd is up for BT or WW again. I occasionally throw in Heroic Throw, and VR if they are available. I have also heard that Demoralizing shout should be used but have not found this has been much help. I should also mention that when my other enrage effects are available I pop those as well.

There isn't a good reason to be silent when you make a change.

Assuming landsoul's fury sheet is using the formula on live, I am getting an ArP cap of ~1220 rating. I can only get about 1000 rating with gear from wowhead though. I wonder if they realized with the ArP change that people would cap too easy and nerfed it without telling anyone. They could double boss armor and no one would notice because it was all ignored.

The .81 modifier vs boss armor is strange design by itself.
The fact that it appears to vary with armor is stranger.

To repeat: Formula is
\frac{A}{A+B((1-Zx)-y(1-\frac{B}{A+B}Zx))}

armor	armor%	Z value	lvl
~9720	61%	0.85	80
10634	59%	0.81	83
13954	52%	0.70	80
21544	41%	0.57	80

This is what I have so far. I used the data I had and used the 'solver' function to solve for the multiplier to x. Because we don't see fractional damage, there's a little uncertainty in these numbers as well. Going to take a bunch more data to nail down a formula for Z that can calculate it using armor or armor & level.
Possibly the best test case will be exactly 10% ArP. So 0 ArP on gear, use battle stance, BT noncrit vs various armor values.

The formula for rating needed to penetrate 1% of target's armor is almost certainly based off the defender's level and not the attacker's level. If you increase the amount of rating needed to ignore 1% of a level 83 target's armor by about 23.5% your numbers should be bang on.

@dysent

I posted this in WoW general, but here you go:

This fits an exact formula:

y = ( a * e^bx) / (c * x)

a = -2.8572402797891482E​+03
b = 3.2184725882343662E-​05
c = -4.0160140627435144E​-03

Where Y = the actual percent ignore and X = the armor. What is buried in here is your ArP amount (either 116.5 or 1445). So either a, b, c OR any combination of them is derived from 116.5/1445. We would need more data points for different ArP to test this, but it is safe to say they are intentionally using an exponential function with linear backoff to calculate your actual armor penetration.

It appears ArP is capped at 8205.75 against bosses according to a new post by GC. World of Warcraft - English (NA) Forums -> 116% Armor Pen only giving 66%!?!?!?!

GC said:

If (level<60)
C=400+85*targetlevel
Else
C=400+85*targetlevel+4.5*85*(targetlevel-59);

For a level 80 target, C=15232.5. For a level 83, C=16635.

The cap for Armor Penetration then is: (armor + C)/3.

===============


So 100% ArP is only possible on a "warrior" target if they have ~5000 armor or less and you have 100% ArP if you're dueling a prot warrior with 30,000 armor and you have 100% ArP you only ignore (30,000 + 15232.5)/3= 15,077.5 or 50 a hair over 50% ArP. Looks like the value of ArP gems just dropped.

Sorry for repeating what others have asked before, but in light of this new information, is it still applicable to stack completely ARP gems into your gear as Arms PVE spec?

I was Fury before the patch, I have +16 STR gemmed into everything. I hit up landsoul's DPS spreadsheet, put in my gear, but not sure if I did everything right - changing all the gems to ARP changed by DPS by less than 1.

In addition, with the same gear, it shows me doing more DPS if I had been specced fury than Arms mace spec. (I'm using a Jawbone for Arms. For Fury, I would be using Jawbone+Armageddon. Never got my hands on a Betrayer, sadly.) I calculated the SEP and whatnot for each. Is this because of the new berserker stance +20% STR? I hopped the boat to Arms hoping to stay in the DPS game for Ulduar and not fall behind with my other guildies.

The only PvE difference this info makes is:
You can't attempt to go above 100% tooltip value.

Other than that all uses of previous formula with .81 reduction work out precisely still.

Also: GC mathed it wrong the first time; the cap is 81% of 11623 (11623 is the correct boss armor, but using the lvl 83 constant of 16635). In other words you can ignore, at most, ~9419 armor on a boss. We should figure out how this interacts with sunder.

Is it appropriate to use the same methodology for PvP? It seems that it would be a little different and we don't have a spreadsheet for that.

What GC says about ArP:

"Okay, here is a fairly technical explanation we put together for how armor pen works.

We didn’t want Armor Penetration Rating to be too powerful against low armor targets, like it had been in BC. We also didn’t want Armor Penetration Rating to be too powerful against high armor targets.

So, we decided on a system where there is a cap on how much armor the Armor Penetration Rating can be applied to. So, the first X armor on the target is reduced by the percentage listed in the Armor Penetration Rating tooltip, and all armor past that X is unaffected. Another way of understanding that is we multiply the percentage in the tooltip times the minimum of the two values: the cap, and the amount of armor on the target after all other modifiers.

Computing the cap is a little tricky unless you are already familiar with how World of Warcraft armor works. There is an armor constant we’ll call C. C is derived as follows (in some pseudocode):

If (level<60)
C=400+85*targetlevel
Else
C=400+85*targetlevel+4.5*85*(targetlevel-59);

For a level 80 target, C=15232.5. For a level 83, C=16635.

The cap for Armor Penetration then is: (armor + C)/3.

A level 80 warrior creature has 9729 armor. C=15232.5. So, the cap is (9729+15232.5)/3=8320.5. Let’s say a player has 30% armor penetration from armor penetration rating and no other modifiers that complicate the calculation (talents, Battle Stance, Sunder Armor, etc.). The game chooses the minimum of 8320.5 and 9729, so 8320.5. That is multiplied by 30% = 2496.15, and so that much armor is ignored. The effective armor on the target is 7232.85 (9729-2496.15). From a player point of view, the armor penetration rating didn’t ignore the full 30%, but instead ignored 25.66%. (85.5% as effective as expected).

These equations should help you be able to test and verify that Armor Penetration Rating is working correctly and as we designed. The tooltip is not actually inaccurate, as it states: “Enemy armor reduced by up to 30.00%.” That "up to" is key.

Please be sure to test without any other effects which modify the armor calculation (Battle Stance, Sunder Armor, Mace Specialization, etc.) as they may involve other systems that add additional complexity to the calculation. "

source: World of Warcraft - English (NA) Forums -> 116% Armor Pen only giving 66%!?!?!?!

Edit: nvm, just noticed someone posted about it first.