I developed this set of instances on 03/Aug/2023 primarily as a party trick to impress @Brokkhouse .
The Roundhouse method of building geometry is by now rather well-known, and well-described in its original thread.
I was thinking about interesting ways to extend the system, and what I realised is that if you look at each piece from above, it's completely flat horizontally - but, there's no reason why you couldn't make it an upward or downward slope - or really any shape - so long as it was still sheared at the 7.5 degree margins.
In fact, you could even make it connect to its neighbours, as long as those neighbours had the opposite slope to the piece itself.

I also noticed that you could divide each piece in half vertically, and have it slope two different directions, for a LOT more variety than the standard Roundhouse method could give you.
My ambitions for this project were originally a lot bigger - I had the idea that you could make the pieces keep sloping more and more upwards, creating more of a spiral than a circle.
That's probably possible, but at the time I thought about it for HOURS and still couldn't figure out how to make the pieces properly connect geometrically.
So, I settled for less.

I don't expect most people to really understand what's going on with these instances.
But, on the off chance you do, the natural question is "do these have a practical use?"
And the answer is "Not really."
It can let you make some crazy zig-zagging geometry, but most of the time you don't really need to do that in TF2 - unless you're making rock walls, in which case displacements will do the job just fine.