Ramblings on tanking history and present itemization (DANGER: 10 page long post ).
I wrote a post on tanking in my guilds forums, having in mind some freinds with tanking alts and offspecs, in which tried to cover basic tanking mechanics. I figured that, having written it all, i might post it here case it could help anyone.
Id like to clarify that i am not trying to be original, and most (if not all) of the ideas in my text i read here in tankspot forums. Additionaly, i am not trying to be a theorycrafter. Being just a "rambling", i do not intend to propose game mechanics that are not already widely accepted. Hence, I am not giving proof for conclusions i make or the assumptions on how game mechanics work, and only attempt to follow a logical stream of thought. Ill be abstaining from any possible following discussion in the replies, though will naturally be thankfull if someone points out something that is conclusively incorrect.
At last I apologize for my poor writing skill. The last time i started a post in the forum, i felt it was very badly received by the comunity and i beleive the blame is in bad text formating and poorly constructed sentances and misspelled english. Im trying to improve this by doing exactly what i am, practicing.
Following is the post as in my guild forum.
Now that i finnaly got full combat table coverage i began to wonder how i would itemize my gear with further upgrades, and felt like "speaking aloud" so to speak, and posting my conclusions here in the forums.
Disclaimers: this was written with mostly paladin tanks in mind. Many concepts apply to all tanks, specially warriors, but there are variations that are not explored or discussed (damage avoidance for non-block tanks, etc).
ctc - combat table coverage
Wotlk - wrath of the lich king
icc - ice crown citadel
cata - cataclysm
oom- out of mana
Case any non-tanks might read this ill give breif explanations on tanking mechanics.
----Basic tanking concepts
Firstly a quick reminder of what tanking means: The tanks responsability is to guarantee the safety of the party or raid team by taking the bulk of the damage. This is done through two basic game concepts.
The first is to make sure the enemy is atacking you instead of your freinds. This is commonly known as threat and i will not discuss greatly as it is presently not a great concern since the recent buff blizz gave all tanks increasing threat generation from 300% extra aggro to 500% extra aggro (from defensive stance, bear form, righteous fury or blood presence).
Ok. so the thing is hitting you. Great. Now your not supposed to die since, if dead, the foe will go back to squishing your freinds. Here comes in the second basic tanking concept which we call survivability. Survivability itself has to be broken down to be properly analyzed:
-Firstly there is Health. This one is easy, when your health reaches zero, your dead. The more health you have, the farther away from zero.
-Secondly there is passively reducing incoming damage. Armor applies to phisical strikes and resistances apply to magical or elemental atacks.
-At last there is avoidance. Avoidace is a RNG (random number generator) dependant defense in which you may or may not take a hit. To better understand them, we must look at how the combat table works.
The combat table
Its a common missconception to think that when you are atacked there are a series of "tests" checking weither you parried, dodged, blocked or the atack missed. To properly prepare your tank its important to understand how a atack is actualy resolved. Blizzard has a giant "table", in our example we will keep it simple and make it numbering from 1 to 100. Each of your defenses is assigned to a series of numbers of this table. When atacked, a random number in the table (in our example 1-100) is rolled, and the atack is resolved acordingly. To examplify: Say you have 10% dodge, 15% parry,20% block and the boss misses you 5% of the times.
The table would look like this:
So if blizzards RNG rolled 60, you took the hit to the face. If they rolled a 7, you dodge it.
Full Combat table coverage means you push hit out of the table by making the other options sufficiently high to fill it in.
A important thing to clarify on block. Block is a avoidance. Its a % chance, and not passive damage mitigation. HOWEVER, when you have full CTC, you can consider every phisical atack against you will be at least blocked. Based on this assumption, theorycrafters consider blocking as phisical damage mitigation *only when you have complete and absolute CTC*, as if it were a phisical damage reduction like armor.
Edit: Tengenstein has pointed out that naming block avoidance is unconvencional and would be incorrect in a serious theoryrafting enviorment. To be "avoidance" it would have to block 100% damage. It is formally seen as phisical mitigation after full CTC, or just "block", a probable mitigation as aggathon named it, if before unhittable.
For anyone curious as why to tanks usualy refer to the magic number 102.4% when reffering to CTC, this is because you lose 0.2% of each avoidance stat each level the boss has over you. For a raid boss its 0.2*3*4 (parry, dodge, block, miss), thus your losing 2.4% avoidance, and must have 102.4% to cover it properly.
During WotLK - Stam stacking optimality
From WotLK to cata, many things changed drasticly. Firstly, having full CTC in Wotlk was impossible exept for Paladins with a special gear set (holy shield used to give giant block chance increase, and have 100% uptime). Even with this, blocking worked differently, and instead of absorving a 30% of the hit, it absorved a fixed amount of damage which, on bosses, was almost irrelivant (any wise-crack mentioning anub should know the unhittable heroic anub tank set was for tanking adds. Im talking about bosses here). Avoidances were further crippled by the chill of the throne debuff in ICC reducing dodge by 20% (dodge was our highest avoidance back then).
Another very important change that severley affected tanking at the time was healers mana. A Healer in WotLK would usualy spam flash heal non stop on their tanks and not go OOM.
This allowed and incentivated tanks to fully gem, enchant and choose trinkets for stamina and properly tank, receiving a constant flow of big heals as their health dropped. Case someone reading up to this point wonders, "Nice, they can get away with stam stacking, but wouldent preventing a hit altogether with more dodge be better?", ill attempt to explain why tanks chose not to further on.
Early on in Cata many tanks (and their healers) suffered from old WotLK mentality. Healers mana regeneration was significantly nerfed with the expantion, spell costs increased, and a healer could not afford to spam flash heal (or whatever fast,big and expensive they had) constantly as before. A healer spamming flash heal would be dooming his party by going OOM. Likewise, a tank who took every hit to the face and forced such aggresive healing to prevent his death, due to itemization choices (stam stacking) also sealed his groups fate.
It became clear that tanks needed to decrease damage intake to be healable consistently throughout a fight. New block mechanics allowed tanks to cover a significant (and later on all) of the combat table, and it became clear blizzards intention was to see tanks blocking hits often.
The critical point - RNG
The problem i see now a days is that just as everyone used to stack stam in icc without knowing why, tanks today stack mastery just because they see others do it or are told to. Stam stackers are shunned universally in memory of early cata in which that early mentality really did prove fatal to many early dungeon finder users.
Why do we need full combat table coverage? Isint 95% of it good enough? After all, you will only get hit 5% of the time. Why is a tank stacking stamina worse?
Imagine yourself holding a 6 sided die and telling me "Im going to roll three 6s in three rolls". Slim chance bud. Its 1/6*1/6*1/6 = 1/216. However, if you hold the same die and tell me "Im going to roll this 10.000 times and sometime you will see three 6s in a row", your making a damn good bet: You have over 99% chance of being right on, simply because of trial and error.
Where does tanking come in?
Its simple. Lets go back to WotLK. Inside ICC, it was impossible for any class to have full ctc. Even if it where possible, a large portion (more then 30%) would be block. At the time blocking was from 1.5K-2.5K damage reduction. Its not hard to see this is not very much when heroic lich king is hitting you for 70K.
Because its impossible to have *full* coverage, during the course of a long fight (Eg: 10m LK fight), you can expect that sometime in there you will see a "worse case scenario". Even if you have 90% CTC, sometime you will get hit 5 times in a row. If you dont have enough health to soak up this damage, to give healers enough of a time buffer to cast their heals on you, your going down. This is why tanks stacked stam in ICC, and they were RIGHT to do it. They couldent possibly prefent the worse case scenarios from happening (by having full CTC), so, they make sure that when they do see it, they arent going down easy.
Now in cata, we have the obligation to get full CTC. We can prevent this "worse case scenario". But once we have full CTC, what then? You could start swaping blocks for crit blocks, parrys, dodges, trying to push out the smaller 30% damage reduction from the table as well!! You could. But its wrong.
Remember the first lines of this post, when we discussed the tanks "job"? If you re-read on survivablity, im sure you already agreed its our "job" to not die. This does not mean its our job to take the least possible damage, and how people are confusing the two now a days, with all of the "omg stack mastery" mentality!
This because, unless you can indeed push out normal block from the hit table (for paladins it is impossible and will alweys be - we cant get 70% dodge and parry to make up for all the mastery), there will still be a worse case scenario in which all of that extra avoidance wont matter! And when it comes, you better have sufficiently high health buffer to take it!
Therefore, after hitting CTC, tanks go back to their old time freind: Stamina.
If someone did not understand or disagrees (im arrogant enough to state that these two are the same thing in this case. You only wont agree if you didint understand), here is a example.
Say your fighting heroic Ragnaros. Both your tanks have full CTC, but tank A has 50% dodge+parry+miss(this is very high), and 180K hp buffed, the other, tank B, has only 35%(average, 15 dodge, 15 parry, 5 miss), and 200K buffed HP.
Now, heroic ragīs fire trap deals 90K raidwide damage, and hits tanks for 70K (this is speculation. reg hits for 60, im guessing 70 on heroic), so lets consider the worse case scenario of having a trap go off and the tank getting hit imedeatly afterwards, and only blocking this atack (both have full CTC, so at least a block they will get). This obviously happens to both tanks since, even though tank A has 15% more avoidance, he still just blocks 50% of the time. This means 130K damage (90K from trap + 40K from a blocked hit). Alhough he can eat these hits with 50K hp to spare, tank A isint in a particularly confortable situation. Hes taking ticks from the tank debuff (normaly damaging from 5K/sec to 20K/sec depending on stacks) and before a heal lands may have as low as 30K hp. if the healer laggs one second and he is hit again, hes dead. Tank B has a more confortable buffer. he can take a tick and another atack before a heal lands and still wont die. Its easy to think of similar worse case scenarios, like your dedicated healer having to run from a boulder on P3, or running to avoid a wave. Its your obligation as a tank to make sure your giving this healer a health buffer that can give him time to do this safely, without depending on lucky rng and having you dodge that critical atack. Anyone arguing "thats what cooldowns are for" is being somewhat naive. Cooldowns help diminish incoming damage you are aware of, and are not alweys available. Worse case scenarios can be unforseen (including human or tecnical mistakes - healer dced, he missclicked, you stood on fire, whatever), and even if you pop a cd on every forseeable one, you will run out of CDs (Eg: cant pop a cd every trap).
Aditionaly, more health might prevent bad mana and cooldown use from healers since, after eating those hits, you will have more health relative to your total, they wont feel desparate. Tank A would get a lay on hands and three flash heals from every healer in range when dropping to 30K(1/6th of his bar). But tank B would still be at 50K(1/4th of his bar, and healers would feel allright to use more "normal", and mana effective, healing).
The fundamental point im trying to make is that you will be harder to heal if you have less avoidance, but, as long as your healer can keep you up without going OOM, its sufficient, and more is a waste unless you can make another drastic change to the combat table. In our example, healers would feel tank A is easier to heal, but tank B will ultimately die less.
He will die less because he touched a vital point in tanking, one that takes a while to realize exists. He is diminishing the impact of RNG. Tanks are a raids first and main shield against bad RNG. You stack mastery early on because you dont want to depend on the chance you will take the hit to the face. At some point, you stop increaing your avoidance simply because health is a safe investment. It might in average make you take less damage, but its alweys there.
Tank B may take more damage then tank A, but he wont leave dying to chance.
Edit: Further down in the discussion thread Airowird pointed out some theorycrafting i was not aware of relating the benefit to survivability by increasing avoidance and increasing stamina. Link to the theorycrafting added at the end of the post. I stand to the concepts explained superficialy on this post, but do not take it as solid proof that stacking stam after CTC is optimal, this may be incorrect.
Well, thats all. Im gratefull to anyone who read all of this and hope you enjoyed it.
Links - further info
My absolute all time favoret post ever on tanking mechanics discussion. Its outdated (written for ICC), but most tanking mechanics have not changed and the concepts here explained are valid and enlightening (I learned many of the concepts im trying to pass from this link).
Also contains imortant concepts such as EH(effective health) and TTL (time to live), which i did not cover due to diminished availability and quality of mitigation stats (armor and resistance).
Weekly marmot treating RNG and how to deal with it, one of the most interesting wow discussions i have ever seen on the net, and that inspired me to use RNG as a argument for explaining tanking principles:
I think everyone, specially our raid leaders (dark, keid) should really really watch this!
Added link (thanks to Airowird -scroll down for his post).