Skeleton Artisan, a specialized branch of craftsman well known by the people, who uses bones of a variety to build all sorts of parts for mechs.
Yes mech parts… That did not include engine parts!
Building a skeleton engine was never something that came across in Ye Chong mind. This was simply because it required to alter the attributes of bones entirely, which could be said in simpler terms - it had gone beyond the artisan fields. To Ye Chong, a skeleton artisan would be one who maximize the strength of bones alone. And the current solution to his problem was already against his belief since it involved permanently altering the bones’ characteristics. They were of two ends of the tangents, not even close in theories. He succumbed to the alteration however since he did not see the flow without modifying the bones.