Talk:VPBE/@comment-24710280-20170414050747/@comment-28433324-20170420092449

That is not how amumu passive works and it is not the reason it was changed.

His passive adds BONUS damage meaning it used to be, in your example, 60 magic damage plus 15% of that in true damage = 60 magic damage + 9 true damage in other words the target would take 69 damage. This is identical in effect to a 15% damage increase in magic damage except for, as you said

After the change the bonus damage is now in that example 10% of 100 or 10 true damage. The reason they changed it is because the intention of the passive rework in the first place was to make it significant against tanks.