Damage Calculations: Deep Wound + Damage

How exactly is damage calculated for skills such as Eviscerate, which inflict a deep wound? Or a Mesmer who uses Phantom Pain followed by Shatter Delusions to inflict a Deep Wound? Here, let me give an example:

Hypothetically speaking, let's take a 1v1 situation:

Player A has 500 health, and is a Mesmer.
Player B has 500 health, and is a Warrior.

The Mesmer brings Phantom Pain + Shatter Delusions. Shatter Delusions dealing 63 damage.

If the Mesmer were to use Phantom Pain followed by Shatter Delusions on the Warrior, how would the damage be calculated? This is how I see it: Deep Wound lowers the Warrior's max health by 20%, which brings him down to 400 health. Shatter Delusions then does 63 damage. So in the end, the Warrior has 337/400 total health.

However, I'm unsure if that is correct. Some people say that it works this way: The warrior has 500 health, then takes 63 damage from Shatter Delusions, bringing him down to 437/500 total health. Each is then reduced by 20%, respectively. (20% of 437, 20% of 500) which would give an end result of 350/400 total health.

Which method is the correct way? True, the difference is not very large, either way, but I would still like to know.

Thanks in advance.

I started a whole big thread about this and I think the consensus was that the damage inflicted by deep wound is 20% of his max hp.
so, it'd be the previous.

The question is irrelevant, because it makes a mistaken assumption about the effect of deep wound. Acquiring a deep wound lowers both your max and current hp by 20% of your max hp, regardless of how close to max your current is when the deep wound is received. (A deep wound can't lower your current hp below 1, however.)

Right. So the scenario I was trying to describe in my original post involved starting at 500/500. With a deep wound, it becomes 400/400.

My question was...if you used Phantom Pain and Shatter Delusions, would the Deep Wound be calculated first, THEN the -63 damage from Shatter Delusions? (400-63 = 337/500)
Or would it be 63 damage from Shatter Delusions, THEN lower both your max and current health by 20%? (500-63 = 437...THEN lower by 20%)

a lot of times i get warriors who inflict a deep wound on me, and i am left with 1 hp. this leads me to believe the damage comes before the % of health reduction.

Again, your current HP is lowered by 20% of your max hp. It doesn't matter which comes first, because either way you're losing 100 hp to the deep wound.

The Deep Wound triggers after the damage (usually) and takes off 20% of max HP from current and max. The target would be left at 337/400 in both cases.

Deep Wound can reduce you to negative HP totals, but it doesn't trigger a check for death. You need to have another HP change before the game checks to see if you're alive or not. Natural regeneration can kick in and return you to a positive hit point total before you die, or a sufficiently large amount of healing can do the trick. But if you're at -80 HP from a Deep Wound and get a heal for 60, you're going to drop dead.

The same effect happens when Endure Pain expires, amongst other things.

Peace,
-CxE

Wow, that explains a lot of weird things I've observed. Good to know!