void staff
does the 40% apply before flat magic pen
or after
does the 40% apply before flat magic pen
or after
Before so you get the maximum effect: 100-40% => 60 - (15+18) => 27MR ^^ Fun fact - It was the other way around during the earlier days of League.
And while we're at Math League-Version: 27MR mean 27% more effective HP on your target so you'll need 2540DMG to kill a 2000HP target instead of the 4000DMG you would have needed without Magic Pen or the 3200DMG you would have needed with just a Void Staff. =P
oh nice thx now i know to build void staff against people who build mr not necessarily tanks