Guild Wars 2

1) Damage Reduction
a) Protection = 33% damage reduction
b) Toughness = 2564~3689 armor = 50% damage reduction
c) Frost Aura = 10% damage reduction
d) Weakness = 25% damage reduction

How does damage reduction stack, So a damage taken calculation would be:
(Weakness from every other attack X Incoming attack damage) X 100%-(Protection+Toughness+Frost Aura)
(0.75 X Incoming attack damage) X 1-(0.33+0.5+0.1)
(0.75 X Incoming attack damage) X .07
or would it be more like
(0.75 X Incoming attack damage) X 1-(1.33 X 0.5 X 1.1)
(0.75 X Incoming attack damage) X 0.27
or am I completely wrong in both cases?

First, remember that Weakness is not a standard damage reduction and its effectiveness actually varies with Precision and Ferocity (because if a crit becomes a glancing blow, damage dealt is half of a non-crit).

As for the rest, I’m not entirely sure. I believe each multiplies separately, though. Weakness definitely multiplies separately from the rest.

I am pretty sure it is multiplicative

However, you do have to make a distinction between % damage reduced and overall % damage reduction, they are both different.

Toughness I believe operates on the principle of overall % damage reduction. For example with an x amount of toughness you have 50% damage reduction.

Things like Protection and Frost Aura I believe operate on the principle of % reduced damage.

So if you have a 50% damage reduction, that means 50% of the damage is inflicted upon you

This means that you multiply the 50% damage inflicted upon you by the 33% damaged reduced from the 50% damage reduction. This roughly equals about 16.5% extra damage reduction. Then you multiply the 50% damage inflicted upon by the 10% damage reduced. This equals 5% extra damage reduction.

You add this up and in total this equals 71.5% damage reduction.

Which means with protection and the aura, you gain a +21.5% damage reduction.

If an attack does 1000 damage, armor reduces it to 500, protection + frost aura reduces it further to 285. Due to it being multiplicative

Weakness cannot be used in this calculation because it is a reduction of the damage output that the opponent is putting on you, so therefore depends on his damage. It isn’t a % damage reduction on yourself

As a more extreme example, if you have 99% damage reduction from armor. Protection and Frost aura will only add roughly around 0.38% damage reduction. 1 damage would only be reduced to 0.62 damage.

At least, I think that is roughly, or similar to how it works, although i might have made some mistakes.

To be clear, though, Toughness is not an “overall damage reduction” like that. 50% damage reduction is actually just 2 armor compared to 1 armor. What killahmayne is refrencing is more like how armor works in League of Legends (incoming damage *(100/(100+armor))) than how it works in GW2 (incoming damage/armor). Having 2k armor means you take .05% of the incoming damage.

http://gw2buildcraft.com/calculator/warrior/

If you look at this website right here, it will tell you the overall damage reduction based on the toughness you have. It uses 1836 armor as the reference point. 1836 armor basically means you take the most amount of damage that is possible. If you double that that basically means a 50% damage reduction. because 1836/3672 = 0.5. Toughness gives you your overall damage reduction from which you apply stuff like protection and frost aura. It is basically a measure.

I am not referencing at all that armor works like (incoming damage * (100(100+armor))). GW2 is incoming damage/armor, but that armor is based on a % overall damage reduction value from the base of 1836.

And having 2k armor means your damage reduction is at 8.2%, which means you are still taking 91.8% percentage of the damage inflicted on you. This is because 2k armor is an 8.2% increase from 1836 armor, which is the base value (0% damage reduction). It is rather simple really.

Thank you for the help and to continue the question do either of these formulas look correct to you?

So according to you killahmayne.9518 would this be the correct formula?
(Weakness X Incoming non-critical damage + (Incoming critical damage)) X 100% – (Armor X (1+Protection))+(Armor X Frost aura)

(0.75 X Incoming non-critical damage + (Incoming critical damage)) X 1 – (0.50 X 1.33)+(0.50 X 0.10)

And according to you Drarnor Kunoram.5180 this would be the correct formula?

Total Incoming Damage -Total Incoming Damage X Armor – Total Incoming Damage X Protection – Total Incoming Damage X Frost Aura – Weakness X Incoming non-critical damage

Total Incoming Damage -Total Incoming Damage X 0.5 – Total Incoming Damage X 0.33 – Total Incoming Damage X 0.1 – 0.25 X Incoming non-critical damage

EX. First attack
21,000 – (21,000 X 0.5) – (21,000 X 0.33) – (21,000 X 0.1) – 0.5 X 14,000
21,000 – 10500 – 6930 – 2100 – 7000
0 Damage taken

Second attack
21,000 – (21,000 X 0.5) – (21,000 X 0.33) – (21,000 X 0.1)
21,000 – 10500 – 6930 – 2100
1470 damage taken

killahmayne.9518:

http://gw2buildcraft.com/calculator/warrior/

If you look at this website right here, it will tell you the overall damage reduction based on the toughness you have. It uses 1836 armor as the reference point. 1836 armor basically means you take the most amount of damage that is possible. If you double that that basically means a 50% damage reduction. because 1836/3672 = 0.5. Toughness gives you your overall damage reduction from which you apply stuff like protection and frost aura. It is basically a measure.

I am not referencing at all that armor works like (incoming damage * (100(100+armor))). GW2 is incoming damage/armor, but that armor is based on a % overall damage reduction value from the base of 1836.

And having 2k armor means your damage reduction is at 8.2%, which means you are still taking 91.8% percentage of the damage inflicted on you. This is because 2k armor is an 8.2% increase from 1836 armor, which is the base value (0% damage reduction). It is rather simple really.

What you’re saying here is incredibly misleading, although technically mathematically accurate.

Just rely on the damage calculation:

Damage = (Skill Coeff * Power * Weapon Damage)/Armor

That’s how it is calculated. You can calculate % reduction based on some arbitrary baseline armor value, but it’s really misleading to talk about % reduction from armor in that fashion.

So here’s what the total damage equation would look like:

Incoming damage = [(Skill Coeff * Power * Weapon Damage)/Armor] * (Crit Modifier if applicable) * (.5 weakness modifier if applicable)

So there’s your incoming damage. Notice that both Armor and Weakness values/modifiers are in that equation. Now let’s go for reduction.

Total damage taken = Incoming damage * (.66 protection modifier) * (.9 Frost Aura multiplier) * (.5 Iron Hide Modifier) * (.5 Phantasmal Defender modifier) * etc etc

I think you get the idea. All the damage reduction modifiers are multiplied with one another, not added separately. This means that it’s not possible to reach 0 damage. With Iron Hide and pDefender you take .25 of the total damage, not 0.

Ah, Thank you very much Fay.2357

it used to be additive among several of the possible mods (ie.. iron hide + protection + frost aura + 1 other 10% modifier = take 0 damage from power attacks). when did it change?

insanemaniac.2456:

it used to be additive among several of the possible mods (ie.. iron hide + protection + frost aura + 1 other 10% modifier = take 0 damage from power attacks). when did it change?

Pre-beta weekends, probably. Having a Guardian potentially being totally immune to direct damage while using a flame ram (and having allies blast ice fields) is pretty broken.

As it is, I haven’t seen evidence of damage reduction sources being additive.