User blog comment:QuantumFeint/Miss Fortune Minor Rework/@comment-10764129-20150621113335/@comment-24558666-20150621115442

You need to realise this 1) AP MF deals magic damage only through E (well she deals some through W, but that is really low). Ultimate is physical damage. Against meelee target(with natural MR/lvl) with 200 mr, this penetrates 60 MR, increasing damage against tanks of this spell by roughly 25%. It is also damage over 3 seconds. Its like if you give inbuilt last whisper to katarina/akali. It has some impact, but it seems bigger on paper than what it is in reality.