Hello everyone! A long overdue update to this thread has now been made. Many changes were made, lots of values got changes since I last updated this and the new champion point system changed a lot as well. But lets get into it.
CALCULATIONS:
We will start off with the base calculations with only your own mitigation. There are two main ways that mitigation works, BEFORE or AFTER a damage shield has been hit. This means that some sources of mitigation will reduce the damage taken before a damage shield takes damage from the attack and others will reduce the damage that overflows from a potentially depleted shield. However, if there is no damage shield then all sources count as being on the same level. The only known sources of mitigation AFTER a damage shield is the base blocking mitigation and any source that says "increases the amount of damage you can block by x%" or similar, all other sources of mitigation is applied BEFORE a damage shield.
Now with the change of the champion point system there are some sources of damage mitigation that stack additive together before being multiplied in. Hardy/Elemental Aegis+Preparation+Duelist Rebuff/Unassailable/Enduring Resolve. These stack together. Hardy and Elemental Aegis obviously can't be used at the same time cause of the different damage types, however the 3 damage forms work differently depending on how many are used. Enduring Resolve can work at the same time as Duelist Rebuff or Unassailable however only one of them can stack additive with the rest at any given time, the other one gets multiplied in as a separate source. They stack additive with the one that has the largest value if their values differ. Juggernaut is the only non block related Champion skill that does not stack additive with the rest, it acts like a unique source.
The other two Champion skills are both related to blocking, "Fortification" and "On Guard", they both stack additive together with all other sources of extra block mitigation. They can all work at the same time, and stacking multiple sources can give you quite a lot of mitigation. With the addition of the advanced stats screen its really easy to keep track of how much block mitigation you got, it will even do the calculations for you. One thing to note though is that "On Guard" will only be added to that stat if you are currently CC immune, and skills like Bound Aegis and Immovable will only appear while the skill is active. Deflect bolts however, being situational to only ranged and projectile will not appear at all, so has to be taken into account by yourself. Now something else fairly important for some to know is that blocking mitigation is capped at 90% this is cause it was possible to achieve mitigation past 100% making you immortal. Had that not been implemented, with this update, it would have been even easier to pull off, I got 107.5% without really trying. Oh and the current advanced stat screen will still show values past 90% for some reason, should probably be looked at.
The heavy armor bonus that grants extra blocking mitigation, behaves in a way I was not expecting. Instead of being additive with all the other sources like previously mentioned it is added into the blocking mitigation after the extra blocking mitigation has been multiplied with the base blocking. This prevents some of the diminishing returns on the bonus, making it much stronger than one might first see. The light and heavy armor bonuses for magical or martial mitigation is applied additive to the base mitigation making them slightly stronger as well. Lastly before showing and example of the formula I will mention that we now have a 10% base mitigation applied to us at all times and battlespirit for PvP has been reduced to 44% instead of 50%.
Total Mitigation=100-100*(1-Battlespirit/100)*(1-Base Mitigation+Light Armor or Heavy Armor/100)*(1-Mitigation #1/100)*(1-Mitigation #2/100)*(1-(Resistance/660)/100)*((1-Blocking/100)*(1-(Extra blocking #1+Extra blocking #2)/100)-Heavy Block/100)
Damage Taken=Base Damage*(1-Battlespirit/100)*(1-Base Mitigation+Light Armor or Heavy Armor/100)*(1-Mitigation #1/100)*(1-Mitigation #2/100)*(1-(Resistance/660)/100)*((1-Blocking/100)*(1-(Extra blocking #1+Extra blocking #2)/100)-Heavy Block/100)
The way you would use this template is to replace the place holders with the percentage numbers that is show in the tool-tips in the game and obviously the resistance should be the number of which ever resistance you want to test with. If you have more sources then just add more to fill your needs in the same way that is shown. Now something you might notice is that this way of calculating will result in diminishing returns, what that means is that for each added mitigation source the usefulness of each individual source gets reduced. As an example, having 2 sources that give 50% mitigation will give you a total of 75% mitigation. This now again has an exception with extra blocking mitigation and certain CP as they stack additive with one another, to add in the additive CP into the form just copy the way that extra blocking is done.
Lets do some examples using things the average tank would use. Lets make it a Dragonknight, for obvious reasons. So they would have 50% from blocking, lets say 40% from resistance, 5% from minor maim, 10% from the Iron Skin Passive and 20% from the Sword and Board Passive and 10% from base mitigation. The calculations would look like this:
100-(100*(1-5/100)*(1-10/100)*(1-(26400/660)/100)*(1-50/100)*(1-(10+20)/100))=82.045
So with all of those sources added together we ended up with a total of 82.045% of the damage we take being mitigated. Now if we want to apply these calculations to see how much damage we would be taking from a hit we would just change it to be like this:
150,000*(1-5/100)*(1-10/100)*(1-(26400/660)/100)*(1-50/100)*(1-(10+20)/100))=26,932
As you can see, even though the base damage we would have taken without mitigation was really high, just a few sources can drastically reduce the damage taken. Now I want to show you guys how this type of calculations would work if a damage shield was involved, cause as I previously explained blocking only mitigates damage that overflows from a depleted damage shield, while everything else will mitigate damage before the shield gets hit. If we use our previous example as our base but then add in a damage shield with the strength of 5000 it would look like this:
(150,000*(1-5/100)*(1-10/100)*(1-(26400/660)/100)-5000)*(1-50/100)*(1-(10+20)/100))=25,182
In this case Minor Maim will hit first, as it applies to the attacker rather than the caster, secondly we have the base mitigation, and third resistance which was previously grouped with blocking but has since Murkmire been moved to be BEFORE the damage shield takes damage. Everything else mitigates damage AFTER the damage shield. Now on to the next bit in terms of calculations:
VULNERABILITIES:
Now since last I updated this thread vulnerabilities have gotten a big change. For those that don't know, vulnerabilities are effects that increases the damage that you take. With the changes to Light and Heavy armor we got 2 new sources of vulnerability, as wearing light armor makes you take 1% extra martial damage per piece and heavy does the same for magical damage. Now the way that vulnerability used to work is that they used to be additive together and then the first few mitigation sources would subtract them, this has changed slightly. What happens now is that vulnerability affects the base mitigation that you have. So for example if you have your 10% base mitigation with 5% from say Minor Vulnerability then you get only 5% base mitigation. Whats interesting here though is of course that the light and heavy armor bonuses also works upon the base mitigation that you have. So if you have your 10% base and get attacked with magic damage while under Minor Vulnerability but you have 5 pieces of light armor then you get to keep your base 10% as the 5% from light armor removes the 5% from Minor Vulnerability.
Now when the vulnerability outweighs the base mitigation then you obviously start taking a bit more damage. Something like Stage 3 or 4 Vampire against fire damage would do the trick on that. Now let me show you two examples. One with 7 Light bonus against Minor Vulnerability and then 5 Light Penalty working with Stage 4 Vampire
Total Mitigation=100-100*(1-(10+7-5)/100)=12%
Total Mitigation=100-100*(1-(10-7-20)/100)=-17%
Last one would show that you would take 17% extra damage. Any extra vulnerability would be added on just like in example 2. Now lets show how this would work from the last example we used with Damage Shields. We will add Stage 4 Vampire and Heavy armor Penalty.
(150,000*(1-5/100)*(1-(10-7-20)/100)*(1-(26400/660)/100)-5000)*(1-50/100)*(1-(10+20)/100))=33,262
RESISTANCE:
So there are two main types of resistance which are Spell and Physical, but each of them also have sub categories. Spell resistance has Flame, Frost and Shock resistance and Physical has Poison and Disease resistance. Now one important thing to know about resistance is that there is a Hard Cap, that means that after you reach a certain point it won't give you anything extra. For Champion point 160+ characters the hard cap for resistance is 33,000, or 660 resistance per 1% mitigated, which then tops it of at 50%. You can have more resistance than what the hard cap allows but it won't give you more mitigation, however, in PvP if someone debuffs you then having resistance above the hard cap can sometimes allow you to stay at hard cap if the debuff is to weak or your buffed resistance is strong enough.
Another thing we need to address now is how those sub categories work with the main resistance types. Sub categories adds to their main type whenever the attack element is of the same element. As an example, if I have 15000 spell resistance and 5000 flame resistance then if I get attack with a fire spell then I will have 20000 spell resistance against that attack. One thing to note here is that if your Spell or Physical resistance is already at hard cap then your sub categories will not add anything, since they are just temporary increases to the main type if attacked by the right element. But again if you get debuffed then anything above hard cap will help you stay up. Last thing to note about the sub categories is that since they are in its base form just adding to their main type then if someone penetrates your Spell or Physical resistance then they will penetrate your sub categories too.
One last thing to remember is that even though players no longer has a base 100 penetration the mobs in PvE still do. So when trying to calculate your resistance in a PvE scenario one should always account for that. Penetration is of course a subtraction of your resistance so for example if you have 15000 resistance then against someone with 5000 penetration you only have 10000 resistance and then in PvE if you have 33000 resistance you will still not be at the proper cap as against PvE mobs you only have 32900. But now on to the next part of this thread and last form of resistance.
CRITICAL RESISTANCE:
Now critical resistance works very differently from the other forms of resistance. What it does is it lowers the enemy players critical hit damage modifier. A characters base modifier is 1.5 which means that if you land a critical hit then you deal 50% more damage. There are ways to improve this, such as minor and major force. What we are gonna be looking at of course is how we can reduce that modifier. This one is yet another subtraction one. Your critical resistance will lower the attackers critical modifier by a rate of 1% for every 68 critical resistance. This means that to remove an attackers base critical modifier you need 3400 critical resistance. It looks like this:
CRITICAL MODIFIER=1.5+(Critical Damage Buff #1/100)+(Critical Damage Buff #2/100)-(Critical Resistance/68/100)
Damage Taken=15000*(1.5-(1700/68/100))=18750
As this is the final calculation I will add this into our previous example and see how it all works in its entirety.
(150,000*(1.5-(1700/68/100))*(1-5/100)*(1-(10-7-20)/100)*(1-(26400/660)/100)-5000)*(1-50/100)*(1-(10+20)/100))=42,015
I will add here though that 150,000 base damage is PvE numbers and PvE mobs cannot critically hit, but it goes to show that even just 25% extra critical damage can deal a lot more damage if your mitigation against it is not enough.
As a final note, I probably have a bit more to test to double check all possible combinations but I wanted to get this update out there, if you see anything wrong in the thread that I need to edit then let me know, and obviously if I messed up big times or forgot to test a specific scenario let me know.