What the hell is the big, black spidery looking thing with claws that fights a mantis on the website?
I have not seen an image, but would guess it would have to be a whipscorpion. If not, possible a sunspider - but you describe claws do I would guess whipscorpion.
Yeah, that would be a whipscorpion. I looked the thing up and... damn, I know I hate arachnids for a reason.