Then he still needs to crap out 99 more sources. Otherwise his argument about Bethesda being "uncreative" is invalid.
If it's in only
one source that can be named, then it's very creative because it hasn't been done a lot.

What for a strange argumentation. A hundred times is a common saying, of coures i have not seen it a hundred times. I haven't even seen Orcs a hundred time in other games or films. But that doesn't make them something new. And so with this Vampire lord. I actually see it in other universes, an it is simply relative common.
And the point is, in TES there are others vampire mentioned in the lore, like the Vohikar who are something special, why not making some awesome nordic Frost Vampires? Why taking a relativ common thing that is never mentioned in TES but is already see exact in this way for example in Van Helsing.
I don't flaming, I simply don't understand this descision by Betheseda, I call this vampire lord uncreative - simply my opinion.
Other thing, a dwemer crossbow - really want that.