Hi all,
Here’s a post I made on gw2 guru that I felt could help some people. I’m happy to be corrected on any of it, but for now I hope at least a few people get some help from it.
Damage formula (best guess so far, appears accurate enough….)
(P + M * 35) * WS * SC / (T + D) = Total Damage
P = Power, M = Might Stacks, WS = Weapon Strength, SC = Skill Coefficient, T = Toughness, D = defense
We don’t need to know weapon strengths or skill coefficients in order to do comparative tests.
Let’s take base toughness+armor of a warrior; 2127 and assume the output of the damage formula was 2,127,000 to make the math easy. You will take 1,000 damage from this hit after mitigation. (2127000/2127).
It is clear that adding 100 toughness to the base results in the formula changing to 2127000/2227, or roughly 955.
It is then clear that adding 200 toughness to the base results in the formula changing to 2,127,000/2,327, or roughly 914.
It is then clear that adding 300 toughness to the base results in the formula changing to 2,127,000/2,427, or roughly 876.
We can see adding 100 toughness reduced our damage taken by 45, a further 100 reduced it by another 41, and the final 100 reduced it by a further 38.
This is the diminishing returns some people think they are seeing.
However, turn that into EHP terms… (Effective Health Points)
If you had 1000hp and base toughness, you would die in 1 hit.
If you had 1,000hp and +100 toughness, you would require 1.047 hits (1000/955).
If you had 1,000hp and +200 toughness, you would require 1.094 hits (1000/914).
If you had 1,000hp and +300 toughness, you would require 1.141 hits (1000/876).
And you can now see that toughness scales the same way for survivability as power does for damage: linearly.
The major difference between mitigation and damage is that you can double your base power (resulting in double damage) by simply adding 916. The same does not apply for defense because it is made up of 916 toughness (which you can double) and a further ~1000 or so from your profession’s armor class.
Taking the original formula you can see why this is the case…
(P + M * 35) * WS * SC / (T + D) = Total Damage.
Because the bracket on the left (which refers to power plus might stacks) is multiplied by the weapon strength and then by the coefficient.
Call it 2 * 3 * 5 for example.. we know this results in 30. Double ANY part of this… the power, weapon strength or the skill coefficient and you result in double your damage. Eg 4 * 3 * 5 = 60. 2 * 6 * 5 = 60. 2 * 3 * 10 = 60. This means that going from 916 power to 1832 power doubles your damage, adding a further 916 up to 2748 results in 300% of your base damage, or 50% more than you had at 1832 power.
This simpler logic does not work for the mitigation side of things because it is an addition of toughness and defense. rather than a multiplication.
As a contrast to that first 916 power doubling your base damage, you would need +50% crit damage and 100% crit chance to match that return (roughly 2500 points worth of stats!). As a contrast to that second load of 916 power giving you an extra 50% on top of your doubled damage (3x base), you would need either +50% crit damage and 50% crit chance (roughly 1500 points worth of stats) or 100% crit chance at 50% damage (roughly 2000 points worth of stats) or somewhere in-between those two extremes to match the return to dps granted by power. TLDR : Power is my favourite damage stat in terms of bang for buck. To maximise my character I go all out power, toughness and vitality.
Hope this helps at least one person, like I said I’m more than happy to be corrected if any of it is wrong.