User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-76.95.86.12-20120519182004/@comment-31.53.226.53-20120521172622

yes but that is preparing for a seal not actually breaking it. just because he's pulling the strings of that plot still doesn't prove strength just that his plan happened before dicks. and actually crowley and raphael are the main villains of season 6. like you said god issues his orders to other angels like he did with michael to imprison lucifer. however he wouldn't do this if his angels could be killed by the threat such as the leviathans so he may just imprison them otherwise as deaths put it they'd chomp the whole petri dish, which means everything. angels, humans the lot. leviathans are ancient and hungry, angels are petty and powerful but angels rely entirely on their angelic powers, if leviathans are immune to it ( which is likely) they would have no defense and would be eaten or poisoned by the black goo.