Can living machines be built?
In The Series, no. At least not fully. While it is theoretically possible to “grow” living machine matter by cultivating material gathered from existing bioroids and then using that to build a new living machine, the end result would not necessarily have a soul (see above) and therefore would not be a complete living machine. The soul or the spark of life is the key hindrance here. No one but a god could create a life; the closest humans can come is to influence how existing life grows. Therefore, true creation of living machines by human beings is impossible.