Well, first... We have our vision of the Metaverse. While Tom's and Rick's differ in some points, we still have an accurate enough representation to gather a basic understanding of the verse. That said, the only concept really important for this is the concept of layers of reality.
From any point in the endless chain, if you take an arbitrary section off the top layer has authorial power over the lower ones. The Fourth Wall, or one instance of it, exists between such layers to differentiate the top layer as real. To our analysis, we always assumed we were in the top layer of the verse, as we cannot go upward unless we are able to break The Wall, therefore the hypothetical existence of a higher layer is irrelevant.
But, as the post-mortem shows, Mr. A is not fictional. He sometimes appears in Connor's TV screen to yell at him.
Furthermore, he does lie.
We have been assured by the instantiations that they cannot create fiction. And true to form, before Radio Void Rebel, any deviation from assigned behavior resulted in termination by Prime. But, consider this, if the instantiations can deviate from assigned path, does it not mean that they somehow must be able to come up with an idea different from the ones assigned to them? That is, to some extent an effort of creativity, new behavior must come from somewhere, after all.
And, at least the very least Prime, is able to lie. Lies are not observable facts. If he is unable to create fiction, he is, by definition unable to lie. After all, he can't use math, logic or observation to compose false sentences. While you can verify if 2 plus 2 equals 5, that will never show itself mathematically to you unless you actually have the idea to check for it, thus exercising creativity. Or have it told to you that you should check for it, which is a lie from another, but we know Mr. A can lie, so him being misled is something of little use.
While it is possible that his lies are the result of observing the exact same lie being told in a lower universe, as a top layer spectator, he is active and shows initiative in carrying out research. That makes this possibility a great deal less probable.
From that, I do gather that yes, at the very least Prime, Mr. A can create fiction. If you think the screw is enough, stop reading. I'll start driving it now.
Look further into the Post-Mortem for some nice tidbits of info. Like a fun little fact regarding the Wall Piece designs. As well as batman, which was foreshadowed from before GuestUser17 even found out about the ARG... Wait. Weren't the Shards created by the Foreshadow Machine blowing up?
Now, look back at the Metaverse Model thread, we had the Tantrum Plan, which involving wrapping everything up and throwing it one layer down so that we could retcon the Wall into not falling. That's the sort of power an author layer has over it's fiction, after all. But, didn't we suggest at some point that Mr. A could break a fictional universe's Fourth Wall to test our theories on and we could simply retcon it into not breaking due to being top-level to it? Well, guess what? That's just what he did. To our layer.
Sure, the "I BROKE IT" made it clear, but, let the implications sink. Mr. A is not fictional, thus, not lower. He can't interact with this world save from acting through us, meaning he's not physically here. This leaves him at one level above. Since he lies, he can create, and while we could wonder where would he write being in the void... Well, he's the one who portrays himself in the void, along as claiming that the void exists inside the Wall. For all we know he's leaning on his couch drinking some hot coffee and wondering what to do next.
Ladies and gents, from the pieces collected, I do imagine that GM, Player, Crisis... We have been written. Should I start calling him Mr. Author now?
Disclaimer: I'm reasonably sure a lot of us thought about this before. Or at least I think so. I just don't think it was assembled in a single compiled form.
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