Pierce Resists – How does it work?

[Merino]

Hello folks. Can anyone please tell me how the pierce resists on Eriny’s or Traldors exactly do work? The delve says it affects only resists gained from items and reduces them by 5%. What does that mean?
E.g. a player with 26% heat resists from his items being hit by a Mentalist specline heat nuke (Ment using Traldors). If the nuke hits for 100 damage on 0 resists, would it hit this player for

a) 100-(26-5)=79
b) 100-(26/100*95)=75

If scenario b) is applicable then the resist pierce doesn’t seem that important, but if it shaves a full 5 percentage points off the resists it were pretty powerful. So, does anyone know how it exactly pans out?
Thanks for your help

Merino/Yeyi

[Hrymf]

I belive it simple remove 5% of the resists, not 5% of the overall resists, so your first formula will be the right one. And just like any other bonus, it all adds up, so having 10% resist pierce along with the other bonuses is always nice

[Gandelf]

The first formula gives the correct answer but it's wrong because it doesn't work out the percentages. It only works in your example because you use 100 in the formula. If you substituted 150 damage instead of 100, your formula would give 129, which is wrong (it should be 118.5). I think you knew this anyway, but were using a shorthand version of the correct formula, which should be:-
d-((d/100)*a)
Where:-
d = spell damage (from the delve)
a = actual resists (i.e. resists gained from items, minus spell pierce)
I think the above is right, as I've tested in Excel.

[Merino]

Thanks for the input guys, I did not intend to depict the correct formula but have a working example to make clear where my question was driving at. Thanks for supplying the correct formula Gandelf.
So it seems the delve information by Mythic is not precise, it should not read "by 5 percent" but "by 5 percentage points". In consequence this means capped pierce resist is pretty valuable.

Merino/Yeyi

[Poh]

The delve says it affects only resists gained from items and reduces them by 5%. What does that mean?

This isnt really that important as most players got high resists. If you nuke a person with 20% resist + 5% racial the resist on your target is 20% however if the target got 3% + 5% racial it would work as 5% because racial resist isnt removed by your resist pierce. So the resist would work like (item - pierce) + racial

atleast thats how i understand it

[Gandelf]

Yes. All that is affected is resists gained from items that you have equipped. Buffs and racial resists are not affected.

Definitely, the resistance piercing bonuses (especially when accumulated) are extremely valuable to a caster working on his/her template. I would rank pierce bonuses equally with range and casting speed/dexterity cap increase bonuses in importance. Also, there are bonuses to spell damage, acuity cap increases and spell duration which are always good to have.

In the end, it boils down to doing as much damage in as little time as possible. If you can create a template based on this rule, you won't go far wrong.

[Overdue]

If you really wanna get picky he said

If the nuke hits for 100 damage on 0 resists