A detailed introduction on the metal humanoid was written in the book.
"Grade-1 Soulless Metal Humanoid, a unique puppet crafted by soul oracles. It possesses its own consciousness and one can control it via fusing their soul into it. There's a spirit stone formation placed within its body which allows for its strength to be enhanced even without cultivating. If several metal humanoids were to be controlled simultaneously, it would form an incredible fighting prowess. Flaws: ..."
Possesses its own consciousness?
What does that mean?
Could it be that this fellow was still alive? Otherwise... How could it possibly possess its own consciousness?
Zhang Xuan continued reading on.
"... Flaw 4, its soul has been willingly stripped from its body, leaving behind only a sliver of inextinguishable flame of life within its body. Thus, it cannot regain sanity. Flaw 5..."
"Could it be that..." Suddenly recalling something, Zhang Xuan's face darkened.
Just some elaboration on the concept of Red Dust:
It's a reference to the red cloud of dust that rises to the air along with the galloping of the horses inside a bustling city. It usually refers to a life centered around material possessions and so, the skill actually has the deeper meaning of 'reaching enlightenment' as you step away from the facades of life.