there are several bits of exposition that needs t be established for "acolytes" to work as a story. One of those this the portal.
The portal is the place that characters from the game walk in and out of the world of "Acolytes" and the whole point of the world looking the way that it does (that whole thing with the floating rocks).
so, why tell you all of that?
Well, I have been working on the final few backgrounds for "Acolytes" and this was one of the last ones that I had to make before I could move on to programing/writing.
I only have to finish the final demo for the game and then I come on to making all of the content that holds the entire game together.