You asked, and so I shall oblige (not that I have much of an essay but shhh it's fine)
Things we know about the Entity: it's a rock, it's maybe a tiny bit eldritch, and it keeps growing. It also functions as Grian's shop this season.
As previously stated, all of Grian's shops so far have been some form of transportation, supposedly bringing the wares from far-off lands. And while the Entity doesn't seem like it would fit into that category, on account of being a rock, I posit that it very well could be.
Let's look at what we have: the Entity is a rock, yes, but it's not just a rock - Grian's episodes have made this clear. The Entity has been described almost as a living being, growing and changing as time goes on. Grian went as far as to say that it ate most of his water wheel recently, something that normal rocks are not usually able to do.
Now I ask you, dear reader, would the Entity have been able to eat the water wheel if it was not able to get down to the river to do so? Would it have been able to consume without the ability to move? Likely not, unless it is much larger and possibly more magical than previously thought.
And now, this next bit is mostly speculation, but consider: the shopping district this season isn't actually at spawn, which means many shops are probably going to move there from spawn. I wouldn't be surprised for the entity to show up in spawn at some point, but for that to happen it would have to be able to move.
The connection that I'm drawing here is based on the fact that all of Grian's shops in previous seasons have had a running theme, and the entity is one of Grian's shops. In keeping with the theme, this would mean that the Entity would not only be some form of transport, but also something used to bring wares from far off lands. Previous shops have done this in very conventional ways, but the Entity isn't conventional, not at all. Even so, it would need some way to get product from far away. And even if it can move, it doesn't seem to do so that often.
But what do we have in this season that is connected to Grian and supposedly leads to far-off lands?
