Talk:Demon Prince/@comment-71.2.242.159-20170510171154/@comment-4511886-20170521095708

It's not a weakness. Black Knight weapons score a multiplier (1.2x, I believe) when hitting an enemy with the demon tag. This means that the damage is boosted based on the initial damage dealt, so if you hit for 100 damage with a weapon, you'll only deal 140 damage with a Black Knight weapon with the same AR.