User blog comment:Touchinos/"Ouroboros" Discussion/@comment-109.193.122.7-20190308204542/@comment-1031724-20190309015605

I fear this might be true as well. Killing an archangel must take a LOT of power, which he had to draw from his soul, and from the moment they said they'd use that soul extraction spell thing for him, I had a gut feeling he'd use it more, get his grace back, and turn to the dark side.

So, they'll probably be forced to seal him in the box and then place that box in Heaven to save it from collapse.