User blog comment:ThePianoJerk/Lucifer, The Dark Shepherd/@comment-5493192-20140624190403/@comment-7709681-20140624191455

I don't know if you notice it, but his W's secondary passive grants 10 bonus base damage to his abilities for each kill (And the Lord have mercy upon us if he didn't commited a mistake and is meant, instead, to be 10% increase per kill)