User blog comment:Thescarypea/SPN's God is really weak/@comment-26992577-20160531051127/@comment-1975828-20160531231955

I think, there's a possibility God created the first lifeform, and that brought existence to death. God and Amara seem to be vital components to the Natural Order, their existences maintain the most important balance. Only they can end each other.

Other things, like archangels, humans, leviathans, can be killed by special weapons, not necessarily just God or Amara. The reason I think this is because God clearly created SOMETHING before he made Michael, the oldest known creation, but Amara destroyed all of them.

Again, this is just speculation born out of the writers' lack of consistency.