Originally Posted by Lollerman
It applies after everything has been calculated, and flat out blocks X number of damage as it says it does. Hence, how Amumu takes 0 damage from certain creeps when these abilities are used in tandem.
That's good to hear. That kind of damage reduction is only really good if have something in front of it.
However, back to my other question, I double checked, this time in a practice game. This time the dragon dealt 56 damage without the shell, 39 with level 3 shell (100 armor/magic res). Now I have three points in Harden Skin, but I that's only two points of damage reduction. Something is off, since 100 armor should have cut that 56 points of damage in half, down to 28 or so.
Either shell is bugged, armor/res is bugged, I'm mistaken somehow, or the mechanics page needs to be updated because it's not working as adertised.
I mean, really. If I'm only gaining .5% effectiveness for hps, then items that grant raw hp gain are clearly a better investment, since adding hp provides protection against both magic and physical attacks.