It would be foolish to challenge him on my level with my ordinary novice, vampiric Breton mage. But if I could throw Karstaag around a bit, it might help.

I know that he's a spectral frost giant and that it's unlikely, but is it possible to use Vampiric Grip on him?

I don't think so. Perhaps you should try it and report back. Just make a save before you do.

No he completely immune to it.

Yes. Will do.

Oh. I see.

No.

As Vampire Lord, he's unable to toss you around either at least.

Interesting. I know the VL vampiric drain can be pretty devestating. I wonder how well it would work against him?

It tickles him.

Oh well. So much for that idea.

Well, he said he was on a novice mage, so he likely doesn't have the magicka pool yet to spam Vampiric Drain in VL form. The damage it does is based on your Level as well, and having Serana with you removes the Damage Health portion of it, completely killing it's damage if you don't have a mod that fixes that bug. Although, at Lvl 50+ the VL Vampiric Drain spell does 25 Absorb Health+150 Damage Health, so 175 damage total, only subject to mitigation from Magic Resist itself, which very few things have. With the Bloodstone Chalice ability, "Blood of the Ancients", you can also absorb Stamina and Magicka from your target as well, making you able to cast Vampiric Drain more often because it leeches some Magicka back.