In Supernatural so far according to my understanding first Leviathans were created by God(in possible hope to defeat Darkness) but then when God saw their destructiveness he casted and locked them away in the purgatory. Then he went to create Archangels and with their help he finally defeated and locked away Darkness. But according to Supernatural Wiki page god first created Archangels, defeated and locked away Darkness and then he created Leviathans. More specifically according to the page:
Eventually, God would go on to create the archangels, and along with them would trick the Darkness by locking His sister away
With His sister locked away, God began His first attempt at unfettered creation, He would go on to create the first beasts, the Leviathans. However, God became concerned at their destructiveness, and locked them away in Purgatory
I thought that Leviathans were Gods oldest creations to exist (though locked away in purgatory) but it appears Archangels were created before them. Which one is the older among them - Archangels or Leviathans?