Guild Wars 2

Someone asked me in-game whether Bark Skin and Protection stack in a way in which you add them or whether take effect as multipliers. Mathematically, his question looks like:

D = (1-(0.33+0.3))xN

or

D’ = (1-0.33)x(1-0.3)xN

where D and D’ are, in order, the two methods of damage mitigation introduced above. N is the damage you would normally take when above 25% health and without protection.

I ran a couple tests in the mists and it turns out that D’ is the true damage quotient. This means that you will be taking around 46.2% of true damage with both Bark Skin and Protection active rather than 36.7% (33% from Protection + 30% from BS). I crashed because of the new update the moment I finished recording the results, so there won’t be an accompanying spreadsheet, but feel free to confirm this on your own.

Essentially, this implies that BS + Protection are not quite as effective as they seem to be with the true mitigation being a whole 9.5% less than what most people assume to be the case.

Just something to keep in mind. I didn’t see anything on the topic in the wiki and I actually believed until now that it stacked as (33%+30%) instead of the actual case. I hope that helps.

Bark Skin is basically an 11% armor boost. 30% damage reduction for 25% of your hp is:

(.25 / .7) + .75 = 1.107 = 10.7% boost

Dunno if it works against conditions though. If it does, it’s more like a hp boost (without needing additional healing).

Should be 33% + 30% = 63% when under 25% hp with protection.

Shirk.6421:

Should be 33% + 30% = 63% when under 25% hp with protection.

Except it is not… which was the entire point of the post.

Faux Sheaux.6179:

Shirk.6421:

Should be 33% + 30% = 63% when under 25% hp with protection.

Except it is not… which was the entire point of the post.

I think he’s lamenting that fact.

Fortunately that works both ways, our traits that give +10% damage are also multiplicative.

I remember reading something offical that they should work additive some time ago…
unfortunately no idea where it was exactly.

Maybe it’s a bug? Couldn’t hurt to put it on the bug forums to get them to look at it.