Roth963
If I become inactive with this massage, I died
The changes are sometimes too spiritual to just be flesh manipulation.Body cultivation techniques reads to me as specialized biomancy than mutations.
Less flexible but much more reliable than unconstrained biomancy
Iron cattle help with spiritual consumption for example, I think it is some kind of combination, cunage both in our body and soul.
One thing that might point against biomnacy is the children, children of cultivators should inherit most of their parents's biological changes, than against, it is possible sufficiently advanced cultivators are each their own species, too divergent to have children, so they need to make something human because that's the middle point they are both familiar with.
Va is supposedly very beautiful, but she and other young masters don't start off as that much greater than a human, if at all, at least far as I can see.