'It is an upgraded version of Blood Reversion Art.'
'What are you talking about! That art is forbidden by the Great High Lord!'
Blood Reversion Art had a bad side effect that made users lose sanity and become mad. It was strictly forbidden from learning or using, but that was what Yi Burwi was suggesting Chun Yujong to learn.
'No, this one's different. Blood Reversion Art would be so, but our clan has studied and fixed this to remove the side effects. We did have success.'
'But how did you'
'We were ordered by the Leader of the Sword clan to do it.'
'An order from the Sword clan?'
Yi Burwi said both covert operation clans owned by the Sword clan were forced to do many dirty things, including study of the forbidden Blood Reversion Art. But he said that the leader of the Sword clan did not know the existence of the Blood God's Reversion Art yet.