First things first, credit; this model is based more-or-less entirely on the following post by @Atobe_Brick:
My first attempt at executing the concept is also in that topic, but I figured that a new topic was more appropriate for this new design. I’ve actually had this done for close to a year now, but apparently I forgot to share it here:
While I didn’t model any new pincers, I took a shot at a custom carapace piece, and I think it turned out pretty well. Rather than trying to include the Rhotuka in the custom part, I instead made it out of a Bohrok shield attached to a Stars foot. This allows for greater detail on the Rhotuka, a bit of poseability, and greater reusability of the custom carapace piece. It also ups the piece count to be more in line with the other Stars sets.
The part count and poseability can be further increased by making articulated pincers with existing pieces:
However, since the Technic pin piece doesn’t have any friction, the pincers would be very floppy. This can easily be remedied by using 3L pins or a rubber band, but it’s unlikely that such pieces would have been included in an actual Stars set.