User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-190.92.7.204-20150612220839/@comment-3045936-20150614044407

Error on quote. But Lilith was afraid of it according to Sam and it still caused pain to Alastair. But Deadliest I think would equate to most powerful in this instance. As far as I know, Cain is the only demon to date that has killed demons with his own powers not weapons and stated he could kill Angels by himself. Cain needed to be killed by the first blade, if he could be killed by something like an angel blade, than why not just borrow Castiel's. Or use one of the many they have or that Crowley had.