User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-50.54.56.39-20140605025302/@comment-82.39.105.22-20141113103057

"No offense. But that's ridiculous. If a leviathan could kill an archangel they'd have set a Leviathan on Lucifer. "

Err? No one even knew about Leviathans back then, with the exception of Death, and perhaps Michael/Lucy.

On topic: Leviathans>Arch Angels.

Look at it this way; Superman could probably bitchslap a Leviathan through sheer strength, heat vision, freeze breath, etc. But taking on Michael or Lucy? All they'd need to do is warp reality and turn his blood into Kryptonite and they've won. The AAs have significantly more power, but they face the problem of Levis knowing how to flip a switch and turn off their power. Edgar did it to a regular angel and Eve did it to a very powered up Cas, and then remarked that she's old and "knows what makes angels tick" - a claim she made due to her age. Levi and Eve are stated to be around the same age, so Levis also predate angels, just like she does. It stands to reason that they know this little switch trick too. In that event, all the powers that the AAs have is negated by the fact that other than their super strength, they can't access any of it. So the fight turns into a brawl; both sides having super strength/durability, but Levis have their "inject poison goo" trick that seems to kill just about anything.