User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-3481504-20120516180343/@comment-86.159.218.70-20120517140342

yeah but i think it was likely that keeping lucifer and michaels cage was to do with the fact if they were let out they would:

A: want kill castiel for trying to replace god and killing raphael, not saying they could but two archangels are stronger than one.

B: roast the planet probably out of revenge which would take alot of power to rebuild.

its unlikely that michael and lucifer wer stronger than cas as he was immune to an archangel blade, enochian sigils and could break deaths binding link all which prove he is more than an archangel. eve can switch off powers which is practically the same thing as immunity. i assume that like humans they produce goo/blood so if it is toxic to the archangels they would win. but its highley unlikely they will ever fight as there are only two left