Originally Posted by DarthRN
Is this Q&A outdated?
Could someone please explain to me if % armor penetration stacks? For example, if I have a black cleaver and a last whisper, and the black cleaver hits max stacks, would my auto attacks and abilities penetrate 73% of the targets armor assuming I also have the 8% mastery as well?
they stack multiplicative not additionally
so you would multiply the 2 percentages together to get the actual percentage of reduction.
but in your case, you are mistaking armor penetration and armor reduction, the're 2 different things. reduction is applied before penetration. so you do the reduction part first then whatever you have left is what you do penetration