Hellpyre

Try taking a look at the spells themselves; you might see something there ;)

I recommend you look at the Vampire Embrace mod from Morrowind for some inspiration on how this sort of thing can and should be implemented.

To do this yourself, you'll just need to add a keyword to all the items of that type, then give the race a perk that mods incoming damage to a 0% multiplier for weapons with that keyword. Or so I would think.