Do you think carapaces are an actual biological species, or artificial? They seem to only reproduce artificially and are created by the game, so... I have an AU idea where they're basically ball-jointed-doll golems (not using the term golems since that's a specific Jewish folklore thing, but that general kind of being - "construct" is too vague to get the point across).
Yee, I get you. Construct’s a good word but can be kinda vague, especially when the work one is referencing also contains “game constructs” as a thing, which the aforementioned characters may or may not classify as.
It is rather up in the air, isn’t it? It is entirely possible that the carapacians were entirely biological and natural creatures that predate SBurb and were just inserted into the game whole. It is also possible that they are entirely artificial and were created solely for the game and contain no biological nor organic parts whatsoever, just that the vats that we see them in are the method of construction. And of course everything in between. It is rather intriguing, as is their potential relation, or lack thereof, to other game constructs such as imps; and whether the larger and more mutated-looking pieces are themselves ordinary carapaces or if they were instead through some process mutated or re-built over the course of the game.
I also borrow from ball-jointed dolls for my own designs. I meshed different chess pieces, ball-jointed dolls, sugar-shakers, sea turtles, wasps, and a few other things to get something I’m happy with visually. (I still have to figure out a good arm design, so I’m not quite finished yet though)
On the biological side, I am classifying them as techno-organic or bio-mechanical. I intend for them to have a skin/shell that is somewhat plastic-like and iridescent and a highly segmented body with pieces that are swapped out when an individual ages or otherwise earns an upgrade, such as when PM (a pawn) crossed the board and was later queened. Each body section is neatly self-contained and while they serve separate functions they can also have a fair bit of redundancy so that the rest of the body will still live and function for quite a while should one (other than the head) be severely damaged or removed. (as WV experienced when Bec Noir extracted the uranium) On the whole they are very efficient and can survive a very long time without sustenance, as is necessary for those that go into exile.
Of course, none of this necessarily helps you as you prefer to adhere closely to canon.
Canon-wise, I’d guess that Carapacians are likely biotech due to the vats and because biotech has been a running theme in the comic. They are probably coded using some form of DNA, since we have seen that used in the meteors in the making of Bequerel and Doc Scratch. The variants on the same piece in different universes, such as multiple Black Queens and more importantly their associated Archagents points to a set of pre-determined individuals with their own pre-arranged personalities, likely with different potential questlines and objectives like helping Noir with his assassination or WV going farmer/rebel already programmed in. Whether there are a limited number of such pregen’d NPCs and everything else is generated as needed, or if some archetypes may be re-used and scattered around to fill in the blanks, is unclear. As is whether they can reproduce without the vat system, or at least I think it is. I have mentioned that I have not read all of the Epilogues, so I do not know how the Carapacian population has grown on Earth C, whether that would be canon to the rest of the comic or not.