The second part of yin control's description read, "Discern the subtle, distinguish traces; gather and disperse at will"!
Though brief, those words contained more than one ability.
First, under tier-three yin control, yin energy had its own "signature."
To be precise, yin control did not give yin energy its signature. Rather, after reaching tier-three yin control, Chen Miao could finally perceive that signature!
The so-called signature of yin energy was much like the blood of a living person.
Different people's blood contained different information.
A forensic pathologist could compare blood samples to determine whether a drop of blood belonged to a particular person.
Yin energy was the same!
Once yin energy passed through the apertures inside a yin cultivator's body and emerged again, it carried that cultivator's signature.
Previously, yin energy had been nothing but yin energy in Chen Miao's eyes. Now, when he examined it closely, he could identify the differences.
Chen Miao tested this ability on the spot.
Then he discovered something unusual.
After releasing the yin energy inside his body into the room, Chen Miao took control of that wisp of energy.
Through that wisp, he could even use a special kind of perception to trace its source through some unseen connection!
In other words, if Chen Miao found a wisp of yin energy that had come from a yin cultivator's body, he could use it to locate its owner!
If he had possessed this ability back then, why would he have needed the Head-Down Curse to find Shi Manman?
But as Chen Miao continued his research, he discovered something else.
After that wisp of yin energy had been outside his body for more than a minute, it began to be assimilated, even though it had not dispersed.
Chen Miao observed it for a full half hour.