Belarkan wrote:BTW, I fail to see how it can be 15% more EH. 35% less damage under 30% give 0.3x0.35 = 0.105 hence 10.5% more EH...
Because that's not how the math works. Magnusharkov had it correct. It can also be found in the
AD thread in the general forum.
It should have been obvious by the fact that your formula caps out at 30% extra EH. It can be shown to be wrong with a simple example where we consider the limit as the damage reduction goes to 100%:
If you took 90% less damage under 30%, your formula would give 0.3*0.9=0.270, or 27% more EH
If you took 99% less damage under 30%, your formula would give 0.3*0.99=0.297, or 29.7% more EH
If you took 100% less damage under 30%, your formula would give 0.3*1=0.3, or 30% more EH.
This
has to be wrong, because if damage below 30% was reduced by 100% (i.e. reduced to
zero), you'd be unkillable, which is an
infinite boost to EH.
In addition, the current version of the PTR patch notes say that it reduces damage taken below
35% health by 30%.
The appropriate way to calculate it is (health)/(% damage taken). In other words:
(health over 35%) / (% damage taken over 35%) + (health under 35% ) / (% damage taken under 35%).
Health over 35% is just (0.65*health), health under 35% is just (0.35*health). The only difference between the two denominators is an extra factor of 0.7 due to the 30% AD damage reduction.
We can easily factor out our base EH due to talents and other passive effects: EH_base = (health)/(% damage taken). This leaves us with:
EH (after AD) = EH_base * (0.65 + 0.35/0.7) = EH_base * 1.15, for a 15% boost to EH.
Note that if you let the reduction go to 100% in this formula (the 0.7 goes to 0), you do indeed get an infinite amount for your EH, as it should be.