Question about % chance

Hey there. Really enjoying the game so far. Old school D2 player here.

I’m building a Shaman and I’m looking at Storm Touched and Stormcaller’s pact. They both have % chance of +% lightning damage. I’m wondering if these are all separate or if any of these things stack?

Basically I’m wondering if my +20% chance and my +33% chance make a +53% chance for +all my +% lightning damage. Including what I get from other items, etc.

Hopefully that’s clear. Thanks!

No, chances like that case work as an individual per proc. And it isn’t a total %increase, in your example it would be, at +1000% lightning damage, with a 20% chance to +100% from one bonus, and 33% chance to +200% bonus from the other, would still only bring you to +1300% if both triggered that attack.