User blog comment:General MGD 109/Who's the strongest demon/@comment-4628856-20130721224336/@comment-4628856-20130723101855

Well, maybe Azazel was more unique than Lilith: Yes, she was the first demon, but he was the only Yellow-Eyed demon to ever exist (as far as we know.) He's shown impressive immunities, apart from being unable to cross iron, and he did indicate he wasn't afraid of angels. Maybe he didn't think an Archangel would go after him, who knows. And well, I only say that a Seraph could potentially kill him because they're a higher tier of angel, and Cas has shown to be much more powerful after being promoted: He was ready to smite Crowley, who'd become quite powerful at the time. But tha'ts just me.

I think that against Seraphs, Azazel could hold his own for longer, but there is no guarantee. And well, theres also the fact Azazel was the king of Hell for a time: LIlith may have been imprisoned deep in Hell, but she would have still been considered the unofficial ruler of hell. The fact Ruby even stated he was one of two demons on the A-list, the other being Lilith, could mean he's marginally more powerful than Lilith. As I said, it could be like the difference between Michael and Lucifer: It was stated Lucifer was only slightly weaker than Michael. So, this could be the case with Azazel and Lilith, with Azazel being stronger only by a margin.