This is also my take . <| sep |> You good ? , you need anything ? Some wipes ? <| sep |> This is the actual quote from Blizzard Now that multiple buffs and debuffs stack additively , we have implemented a cap . The current cap is set to 75 % on the damage reduction side , and 25 % on the damage amplification side . Now , either that includes damage mitigation or it doesn ' t . If it does include damage mitigation , then it is exactly as I said you can ' t get more than 75 % damage reduction but vulnerability effects can stack . If it doesn ' t include damage mitigation , than a warrior with 25 % damage mitigation baseline becomes damage immune when he gets 75 % additional damage reduction temporarily . My point is that Ignitus 1 is wrong the 25 baseline is part of the 75 cap , but then you can stack vulnerability effects against it to get it down to 25 % more vulnerable . He seems to be under the impression that baseline damage resistance isn ' t part of the calculations .