The MDR Bug

maxicek

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All posts that are not in quotes are from SSog.
Originally posted Apr 17, 2007

The MDR bug.

I'm wondering if anyone has taken a look at it and specificly what attacks it effects. I'm personaly wondering about whirlwind.

What's this MDR bug? o_O

The only "MDR bug" that I know of goes as follows:

If a player has PDR or MDR and gets hit with an attack that deals both physical *AND* elemental damage, and the player's PDR or MDR is enough to negate that specific type of damage, the excess PDR/MDR will roll over and reduce the other type of damage.

As an example, if I have 100 PDR, and an enemy hits me with an attack that deals 75 physical damage and 50 fire damage, then first my PDR will negate the 75 physical. After that, I will have 25 "unused" PDR, which will roll over and reduce the Fire damage, meaning the net result is that in the end, I only take 25 Fire Damage (as opposed to 50, as I was supposed to).

For practical purposes, the only two times this makes a bit of difference is if you're making an extreme PDR rig (80+ PDR), or if you're engaging in Low-Level Duels. In LLDs, people shun elemental damage small charms like the plague, because if they use an elemental damage sc, then suddenly that allows any MDR the other player might have to "roll over" and reduce the physical damage (which is one reason why SoE is such a popular belt in LLDs).

As for what attacks this affects... attack type is irrelevant. As long as any source deals both physical *AND* fire/cold/lightning/magic damage on the same attack, it is subject to this bug.

So on a ES sorc, it's just as good to socket Sols as Mals, as long as you have 1 MDR on something somewhere, and don't get hit by pure fire/lightning/cold attacks?

ES Sorcs usually don't wind up socketing either- they can get more than enough PDR and MDR from preset uniques (Gerke's Sanctuary, anyone?).

Anyway, even if you were to socket, then yes it would be as good under that assumption, but it's a lousy assumption. It's impossible to avoid all purely elemental attacks, and when you finally DO get hit by a purely elemental attack, you're going to get hurt.

i have a couple questions to add to this thread. since i lld a lot my questions are going to concern a fairly typical set up of vipermagi + string of ears (28 mdr total) for most caster characters.

1) is total mdr from all gear used for calculating how much you reduce or is each item taken into account separately. ie from my example above is it 28mdr or is it 13 mdr and 15 mdr?

2) does mdr lower each source of the elemental damage? i'll give an example: one guided arrow from a bowazon using sojs (no other sources of non physical damage). let's say that the guided arrow is 500 physical damage + the 1-12 light damage from the sojs, let's also say that the rolls for both the light sources was low. so is this theoretical guided is 500 physical + 2 light damage or 500 physical + 1 light + 1 light? i'm pretty sure that they're treated separately, but i'd like confirmation. another question based on this; if one small charm has 1-2 fire damage and 1-2 light damage would each element type be reduced? the source of the damage is the same for both types but again i believe that both are treated separately and would therefore be reduced to nothing with a simple mdr 2.

3) how does the magic absorb on spirit work in relation to this bug? does it affect only magic attacks (bone spells and hammers being most common) or is any "magic" attack going to be absorbed?

why i'm asking these questions is because i'm wondering if enough of the charms on the above bowa had elemental damage to cover the mdr on the typical dueler then the bug would be a moot point.

1) is total mdr from all gear used for calculating how much you reduce or is each item taken into account separately. ie from my example above is it 28mdr or is it 13 mdr and 15 mdr?
I don't get what you're asking- aren't those both the same thing? I mean, if you take 28 damage, does it matter if it's reduced by 28, or reduced by 13 and then reduced by 15 more? Either way, it's 0 damage in the end.

2) does mdr lower each source of the elemental damage? i'll give an example: one guided arrow from a bowazon using sojs (no other sources of non physical damage). let's say that the guided arrow is 500 physical damage + the 1-12 light damage from the sojs, let's also say that the rolls for both the light sources was low. so is this theoretical guided is 500 physical + 2 light damage or 500 physical + 1 light + 1 light? i'm pretty sure that they're treated separately, but i'd like confirmation. another question based on this; if one small charm has 1-2 fire damage and 1-2 light damage would each element type be reduced? the source of the damage is the same for both types but again i believe that both are treated separately and would therefore be reduced to nothing with a simple mdr 2.
For both of the following examples, I'm going to ignore the PvP damage penalty, just to keep everything nice and simple.

MDR lowers each element exactly once, regardless of the number of sources. If a person has 20 cold damage small charms that deal 1-2 cold damage, and you have 2 MDR, you will not negate all of their cold damage- they'll still deal 18-38 cold damage to you.

On the other hand, if someone has a 1-2 cold damage small charm, a 1-2 lightning damage small charm, and a 1-2 fire damage small charm, then 2 MDR would indeed be enough to entirely negate the damage. This is why you don't see many LLD Avengers- MDR works at 3x effectiveness against them *AND* rolls over if you have enough, which totally pwns them.

3) how does the magic absorb on spirit work in relation to this bug? does it affect only magic attacks (bone spells and hammers being most common) or is any "magic" attack going to be absorbed?
"Magic Absorb" is not like "Magic Damage Reduced By". MDR works against any non-physical, non-poison damage, whereas Magic Absorb only works against true magic damage (Bone Spells and Hammers, as you said).

why i'm asking these questions is because i'm wondering if enough of the charms on the above bowa had elemental damage to cover the mdr on the typical dueler then the bug would be a moot point.
PvP penalty is 1/6th, right? If that's the case, you'd need to deal more than 168 damage of a single element to overcome 28 PDR in LLD. Pretty much impossible to get via elemental damage small charms, so you're better off just stripping off all of your elemental damage gear in the first place.

thanks a bunch for the response. my first question was just an attempt to make sure i covered everything. i was 99% certain i knew the answer, but i wanted to confirm.

i have two more questions (for now):
1) is poison affected by this at all? a big part of kickers is venom so i'd think if poison was affected that they wouldnt want to use it.

2) this bug applys to pdr as well right? a low physical damge/high elemental damage (say a ranged enchantress) would have the physical portion negated and then the spillover pdr would apply to the elemental portion as well, correct?

1) No.
2) Yes.
 
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