From a technical perspective, carbon-based creatures don't necessarily need metal elements, nor do they need calcium supplements, such as certain extraterrestrial tentacle monsters.
But undoubtedly, humans on the Mechanical Split Star are not included.
In fact, the intelligent species on the Mechanical Split Star are almost indistinguishable from humans on Earth.
Therefore, Aramaki's internal mutation piqued Gao Gong's interest—was it due to some special human experimentation, or cloning? Or perhaps, some unspeakable reason?
For instance, Gao Gong knows that the Arasaka Group has always been in contact with outer space, and the Arasaka Tower has the ability to send signals to extraterrestrial worlds.
Regrettably, possibly sensing the change in atmosphere, as an old hand at this, Arasaka only went through the motions of chatting for a bit before scurrying away—before leaving, he even thoughtfully swapped out luxury carriages for this group of Mother City officials.
