Its based on post-mitigation damage
that means that: buying more magic resist will make you take less damage from Amumu's passive and buying penetration is still important for Amumu's magic damage dealing teammates
the reason it is true damage post-mitigation rather than magic damage pre-mitigation is probably just to make it noticeable.
I just tested this in the practice tool and you are 100% right. When I tested, amumu's E did 100 magic damage premitigation and did 51 damage postmitigation (the dummy had 100 MR). When I cursed the mummy and used amumu's E again it did 51 damage plus 7 true damage. This 7 true damage is 15% of the 51 post mitigation damage which means magic pen makes amumu's passive do more damage and building MR will reduce the true damage you take.
if that were the case, it would literally not even do more damage, so that can't be right at all.
Proof? All other, similar things are done pre-mitigation, no reason this wouldn't be.
Its based on post-mitigation damage
that means that: buying more magic resist will make you take less damage from Amumu's passive and buying penetration is still important for Amumu's magic damage dealing teammates
the reason it is true damage post-mitigation rather than magic damage pre-mitigation is probably just to make it noticeable.
DELETE this thread please. i have never heard something so 100% factually wrong in a long time on these boards, and thats saying something trust me.
