User blog comment:Touchinos/"Ouroboros" Discussion/@comment-31057575-20190308111032/@comment-10889355-20190308115405

It's established that a Nephilim will become stronger than their celestial parent. In Jack's case, more powerful than Lucifer, so I don't know why you're surprised?

Jack wasn't powerless nor his powers were "empowered by soul". He still had his Nephilim powers post-death in Byzantium, he just have to burn off his soul to use it. In this episode, it looks like he burned all, or most, of his human soul to be able to exorcise Michael out of Rowena and ultimately kill him.

It made sense and it was such a satisfying death. I'll take this over that tired ass Michael vs. Lucifer fight last season anytime.