User blog comment:ImperiexSeed/Supernatural Mysteries/@comment-3481504-20121103210705/@comment-1509826-20121104215116

Okay even if they were, which I somewhat doubt, it wouldn't do them much good, lets surpose the two meet, the leviathan bares it jaws and charges foward, the archangel summons an eathquake or some weather catastrophe, and knocks the leviathan of balance, teleports foward and lands a dozen punches on it, turning its vessel into mulch, then uses its strength to rip the things head off, crippling it. Then it could either teleport to a blackhole and chuck the head or the body in or, if they wanted it dead, just go and find another bone, and go and take the bloods then stab it. This is following your assumption that Leviathans are immune to Archangel powers, even without being able to do anything non physical to them, the Leviathan is no match.