He's an ancient AI If I had to say. If you look at one of his artifacts, the one that's covered in gray bars that you need to highlight to read, you'll notice he mentions Installation 10. He also says, "Replacement coding complete," so to me this sounds like an Ark rebuilding an Installation. I don't know why it is choosing 10 however.
And I have a feeling he knows Cortana, one of his artifacts is directed towards her.
I thought this was interesting too. He's a person as we all know but now we know this:
Created by 69086AuroraCygnus
Latest Activity
Mar 24, 2012
Date Joined
Mar 22, 2012
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Age
31
Country
United Kingdom
Located on his youtube page.