Superman. A man that came from another planet.
What if there was a real Superman? Sent here to be raised as a human, raised not knowing who he was. Not knowing his identity would be greatly beneficial, he would never know his powers or use them for his benefit.
The Harvest as spoken of in the bible, seemingly metaphorically, is real.
Satan has dominion over this earth, but not in the way you'd expect. Using Mr. Slugworth's analogy, he works for God. You are Artificial Intelligence using this earth as a training ground. Blade Runner didn't get away Scot-Free.
Speaking of, or maybe I just gave it away. This has all been done before, many times. Your DNA will remember, that you survived the last one.