What "Mutually Exclusive" mean:
a) you can't roll X% Physical Damage taken as Fire and X% Physical Damage taken as Cold on a same item
b) Similar to how Rat's cage work. If you have 10% Physical Damage taken as Fire on helmet and 10% Physical Damage taken as Cold on an armour none of these apply and in the end you take 100% Physical Damage taken as Physical.
External link →I've followed the linked posts for the original explanation of that mechanic as well, and it just doesn't make sense with the last comments I've read from Mark about the mechanic.
/u/Mark_GGG Can you explain / confirm what's actually going on with the interaction of these mods?
They used to cancel each other out - when "taken as" stats were first added, there were only stats going in one direction, and they were used with negative values to indicate going the other direction.
But this meant if you had two opposing ones, instead of both applying, they summed to a total value where one would cancel out some of the other. Initially, this wasn't a problem because no-one had two opposing such modifiers, as they were very rare. But of course that didn't last.
That was changed a while ago so that this no longer happens, and each potential direction od "taken as" is it's own stat that applies separately. I'm afraid I don't have time to find a specific patch number at the moment.
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