how does "of slaying" effect work?

[heluo]

I wonder how "of XXX slaying" (do doubled damage against certain enemy)enchantment works.

Does it doubles every total damage? or weapon's base damage itself(like mater dagger skill effect)?

How does it work if equipped dual wielding?

[Xfing]

I think the only part of damage doubled is the damage afforded by the weapon itself. Which can be a small part of the overall damage result, which also takes into account skill bonuses, strength and spell bonuses. Only the damage inherent to the weapon is doubled, which in practice gives you a small percentage boost to overall damage output.