As you can see, this fellow has a HF skeleton and even the torso piece which I rarely use (except on WIP stands). Of course they are layered with slizer feet and other everyday stuff, but still... And look, there's even some rubber joint supports to hold those giant pincers! I got the idea years back, when I was building the old version of Avde, and finally used it there. Fortunately I got two of Ogel's Mutant Killer Whales as a birthday gifts when I turned I guess 8.
I wanted to keep the legs thin and mollusk-like to create a contrast with the arms and pincers. It created a nice top-heavy look. The tail makes it a bit less human, while a dinosaur arm as a back toe adds support and allows better posing. The back is spiny as crabs use to be.