User blog comment:ImperiexSeed/The oldest being, archangel or leviathan?/@comment-141.136.235.184-20140628224847

Leviathan can negate angelic powers. So Archangels are just humans for them. They can't hurt Leviathans, can not zap away (as told by Castiel in season 8) and will possibly be killed by Levi with no real fight at all.