Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - General bloodrain&bless can't cure historian's necrofire

Just tried to do this, so I failed to hit char w/o arm to get blood and bless it, but there is another way that works.
You can take elf, use Flash Sacrifice then bless her and then Netherswap with Historian
Worked out for me