Transforming the soul of a Journeyman Mech Designer into a 'demon' was not that simple.
As a spirit derived from a human who had barely passed the threshold of the first major cultivation rank, it was easy to go overboard and break it outright.
Souls were normally fragile existences. Without any of the vitality and protection that came from occupying a living body, they became defenseless and could wither away at any moment.
Perhaps that was why Demoncasting and Demonforging centered around the use of demons as opposed to uncorrupted souls.
The former had already undergone a process of demonization, which caused them to undergo a bizarre transformation that radically strengthened their substance.
Even if the mutations caused the souls to become ugly, corrupted and irrational, they also gained a lot of strength and endurance, allowing them to withstand punishment that they previously could not endure!
