It is always multiplicative, imagine if you have 3 conversions say skill modifier, skill transmuter and global conversion with 50% conversion in each step. Your total conversion would be 0.5 + (1-0.5)*0.5 + (1-(1-0.5)*0.5)^0.5
It converts Lightning to Pierce and Physical to Lightning. Question is, in what order do these conversions occur? Afaik a specific damage type can only convert once, so I guess Lightning is first converted to Pierce, THEN physical is converted to Lightning so you end up with unconverted Lightning even if the item rolled 100% Lightning to Pierce conversion. Or am I missing something?
With the stat rolls on that weapon, you’d have leftover Lightning that can be converted because of the Lightning->Pierce conversion, Pierce damage that can’t be converted, leftover Physical damage that can be converted because of the Physical->Lightning conversion and Lightning damage that cannot be converted again.
If you had 100% Lightning->Pierce conversion, you’de have Pierce/Lightning damage that cannot be converted again and leftover Physical damage that could be converted further.
Conversions on the same level are additive, on the different - multiplicative. Item skill modifiers and skill transmuters are on same level, elemental conversion has a priority over fire/lightning/cold.
This may confuse newbies (talking about myself, since I had this doubt).
While it is true, it should be noted that once, means your 100% damage can be converted only once. But 1 thing converting 30% of your damage and another thing another 30% and then another 40%, counts as once. So you could say each “unit” of your damage can only be converted once.
At least this is what Ive understood, correct me if Im wrong.
As Korsar stated before, elemental damage takes precedence to individual fire/lightning/cold in the conversion order. So it would be logical for it to happen the way you described it. Then again, haven’t tested it myself, so i guess we’ll have to wait for a confirmation.
Btw, welcome back, i wasn’t signed as a user when you were active, but i always enjoyed your posts on the forum
Im still new at this, but for what Ive read, conversions of the same level (in this case, items converting a non skill specific damage type) are applied scaling the percentajes.
So if you try to convert 90% and 25% of a damage type, it will scale 115% (the sum) to 100% and apply the respective scaling to the 2 percentages:
you would convert 78,26% to physical and 21,73% to chaos
EDIT: Im talking about what happens when you convert over 100% of the damage, not taking the elemental vs fire of the original damage into account