How does it work? Is it specifically for things like Skyfall and TNT? Or does it add extra damage absorbing ability for any type of attack?
Dictionary says that X percent of your all resists applies to damage taken by mana shield.
If you have 1000 resist and 20 points in Infusion then 100% of resist applies to damage taken. If I have 100k mana (not to mention barrier talent points) then what would that equate to?