Talk:Kog'Maw/@comment-70.79.143.203-20110817185926/@comment-1663379-20110818123432

9 magic pen increases about 5% damage for your magic damage against enemy with 30 MR(most of champion) and even lower with more MR(like most of melee champion that get 1 MR per level), but it's higher against lower MR(when you use Q)

But, I find out that armor pen rune work more effectively because you can attack enemy without use your mana.