User blog comment:General MGD 109/Who's the strongest demon/@comment-26992577-20151006124000

In terms of invulnerability: Cain > Dean > Abaddon > Lilith > Alastair > Samhain > Azazel > Crowley > Astaroth > Crossroad Demons > Average Demons

In terms of abilities: Cain > Lilith > Azazel > Crowley > Alastair > Astaroth > Samhain > Abaddon > Dean > Crossroad Demons > Average Demons

With Cain so powerful, I think he could at least smite Gabriel or Raphael.