Which Metagem to use
Sorry for my bad english right away.
Today I did some math on the two meta gems available for Tanks.
+81 Stamina +2% Armor
+81 Stamina +5% Block
Since 5% Block is bugged it's only 1% .
The Armor values are just pre-made numbers to make the math a little more handy, but they are quite close to mine in a Raid. The other Stats are exact ones.
So we start with +2% Armor!
40000 Armor with armor Gem: ~55,117% -> 44.883% incoming Dmg left
39215 Armor with block Gem: ~54,626% -> 45.374% incoming Dmg left
44.883 / 45.374 = 0.9891
Taking these numbers is a DMG reduction of ~1.08%
12,05% Dodge (pre DR) = ~10,57% Dodge post DR
15,30% Parry (pre DR) = ~12,86% Parry post DR
Since Bosslvl is 88, you need 102.4% Avoidance to be unhittable.
So a Boss hits to 73.97% with his melee swings.
1.08%*0.7397 = 0.7988% effective DMG reduction from Austere Shadowspirit Diamond.
Now the Eternal Spiritshadow Diamond
30% Block value
52.01% Block Chance +8.33% (Shield Block 33% Uptime)
Based on data on World of Logs I have a Crit. Block Chance of ~37%
30*0.63+60*0.37 = 41.1% Block value average
By inserting the Block Meta Gem I'd gain 1% Block value and 2% critical Block value.
31*0.63+62*0.37 = 42.47% Block value
An increase of 1,37% Block value which in my case happens 60.34% of all swings.
Shield Block used on CD:
1.37*0.6034 = 0,8266% effective DMG reduction from Eternal Spiritshadow Diamond
Eternal Shadowspirit Diamond provides 0.0278% more Mitigation if Shield Block is used on CD (in my case)
I'm assuming the Block Meta scales better with gear than the armor gem does, but i didn't do the math
If you find some mistakes feel free to reply
In the example you used you have 28,4% avoidance and 52% block combined 80,4% so you only have 22% to get a full hit, shield block gives only 22% block in that case so it should be 22/3=7,33% block from shieldblock. The rest looks solid :)
Did the math myself with 30% avoidance and 54% block used a bit different calculations but my conclusion was that with the blockmeta i took 0,77% more damage on average in the the 20 secs without shieldblock and 2,37% less damage while shieldblock was up. Making the blockmeta slightly better on avarage but i found the difference not big enough to switch yet since armor meta is more reliable and helps in situations with bad hit strings.
Blockmeta will get better when we get closer to 102,4% unhittable, since the armormeta is only better on the full hits we receive. Think I'll switch after 5% more block but also depends how i value EH, might be that when i start with hardmodes I'm not willing to sacrifice the EH the armor meta gives.
That is a very encounter specific gem, so specific I cannot really think of one I would use it on right now. There is no "sartharion+3 breath" to survive.
Originally Posted by Selene
Depends on the Tank and Spec.
Originally Posted by Nukous
Prot Pally depending on how they spec, don't need the run increase.
also imo the 81 stam/+2% armor > 54 mastery
69 mastery provides something like .57% block.
so it provides 0.171% Mitigation excluding the crit block
Assuming my average block value is like 42%:
-> 0.2394% Mitigation including crit block
Are you sure this is actually bugged? Normally, we block for 30% of the damage. 105% of 30% is 31.5%, which is what the metagem seems to actually do.
Originally Posted by Shaizhowfn
The wording is really vague and seems to make most people think that the 30% goes to 35%, but a lot of WoW +X% adjustments to things that are percentages themselves tend to be adjustments of the actual percentage value, not just added to the actual percentage value. For example, the Abyssal Seahorse mount says "Increases swim speed by 450%". Swim speed is normally 67.5% of running speed, so the Seahorse moves at 67.5% + 450%*67.5% = 371.25% [same speed as a land or air mount that Increased speed by 271.5%]. Notice that it's NOT 67.5% + 450% = 517.5% movement speed increase. Similarly, +5% to our value of 30% is 30% + 5%*30% = 31.5% NOT 30% + 5% = 35%.
Fairly certain the gem does indeed increase block to 31.5% damage reduction and 63% damage reduction on a critical block. Which would probably mean the gem is better than that math suggests, unless I read something wrong.
Not trying to take anything away from this thread.
But I personally choose the armor meta for the same reason I choose to aim for passive unhittable (get as much Mastery as possible). It might end up being less damage reduction "overall", but it's gauranteed reduction - as where the block meta is not.
There was discussion in the T&M forums about this, with some talk regarding Warrior crit block aswell.
When i started with my calculations I also assumed the gem would increase my block value to 31.5%, but after some testing regarding a comment from a guild mate I've found it only gives 31% block value.
Are we sure that this is true? If what you're saying is true, the armor %DR is calculated after parry/dodge/miss/block. I always assumed that it was calculated before, such that Boss Hits -> Damage to be done is calculated based on Armor -> Avoidance Roll -> If Blocked, take 30% off of that mitigated damage.
Originally Posted by Bigbad
Doesn't really matter if you do 0,42(from armor) * 0,7(from block) or 0,7*0,42 answer will be the same.
Does the run speed stack with the "Stam/run speed" boot enchant? If not, I'd take the boot enchant and an 81 Stam meta.
Originally Posted by Nukous
For warriors it seems the block performs better in better gear for 2 reasons:
1) You get progressively closer to unhittable/are with shield block.
2) Hold the Line uptime increases which means critical block frequency increases.
I can't speak for the other tanks however.
I made a calculator for just this question: http://www.bacondev.com/tankmeta/
At lower gear levels Austere wins out. With a couple pieces of raid level gear it will shift to favor Eternal instead.
Paladins need a little higher avoidance+block before Eternal wins but it's still very reasonable numbers.
Pretty sure on the latest patch notes they have changed the stam/sbv to only have 1% sbv
True, they did say that. But it already was 1%. Well, 1.5% rounded down. Instead of 30% blocked damage, you block 31%.
The question is now: did they just make the description go in line with the net effect or did they reduce the net effect to 20% of the previous value. In a comparison between the Austere and the Eternal option, Eternal only won by a narrow margin as it is/was.
I'd guess they only changed the description but left the effect unchanged, because too many people expected the bonus to be additive rather than multiplicative.