[Baalz]

I believe your description is a bit off Kadelake. When blood vengeance triggers the attacker is hit by whatever attack was just negated, including all it's properties. That means if, for instance blood vengeance negates a hit from pillar of fire, then if the attacker is fire immune then he will never take damage. If the attacker has weapons of sharpness active, then he's hit with AP damage. So, weapons of sharpness is quite detrimental in this scenario.