The first impression that these metallic monsters called the Gorgonian Demons by the L'Haronneans gave to Hao Ren was that these were ancient weapon systems that had gone out of control. And it was a technology-based, high level sort of out-of-control weapons, at the same time they too had a very obvious trait... like unique structure of a biological life-form.
Even if the beasts were totally made out of metal, the alloys still resembled obvious muscles, bones and innards structures, and each structure had a logical use to it, and their outer form were similar to animals, and the manta ray, giant insect form were the most obvious trait, and when you get into their insides, this wondrous 'imitation of life' were even more glaring.
