In Hammer of the Gods (season 5 episode 19), we get to see just how powerful Lucifer really is: he dispatches several pagan gods without breaking into a sweat.
Don’t mess with Luci.
Lucifer and Gabriel’s reunion could have been so sweet, but Gabriel has no loyalty to his brother. Poor Lucifer. First Michael, and now Gabriel.
Luci isn’t going to be beaten, but that’s not the way he wanted that to play out.