Ren Qing stayed in the Fireworks Hall for a full seven days before stepping outside again.
Occasionally, when a few horribly mutilated corpses appeared, they were handed over to the Li brothers and Xiao Wu. The three of them had become quite adept at handling such matters.
Ren Qing's primary focus was on figuring out how to cultivate the Skin Book.
Unlike the Eyeless Method, which relied on visualization, the Skin Book required external stimulation—the simplest being physical beating.
If a special medicinal bath could be prepared, it might produce miraculous effects as well.
Of course, the Skin Book likely had far stranger cultivation methods, but Ren Qing certainly wasn’t going to try flaying himself to test them.
At the same time, he was also considering how to advance to the Dual-Pupiled One, though he had already prepared himself to sacrifice another year of his lifespan.
Still, he couldn't help but feel a bit wary of such a bizarre power system.
Ren Qing recalled the things Song Zongwu had hinted at in the prison and decided to investigate his suspicions.
He made some preparations, such as hiding a short blade at his waist and carrying a few pig eyes, then headed to the Martial Arena.
Originally, he had planned to bring Xiao Wu along, but many areas in the yamen, including the Martial Arena, were off-limits to white-robed assistants.
The Martial Arena was shared among the four districts—east, west, south, and north—and covered a vast area.
From afar, Ren Qing could already see quite a few constables practicing swordplay, watched by other yamen personnel who cheered from the sidelines.
His arrival drew sidelong glances—after all, firework attendants rarely came here.
But the attention soon waned.
The constables were all focused on a sparring match between two people in the center.
The two wielded blunted wooden swords, their movements swift and fluid, showcasing swordplay that balanced offense and defense.
Ren Qing watched for a moment and quickly lost interest.
The two clearly had no killing intent—if it had been a real fight, the outcome would have been decided within a few moves.
He walked toward the martial tower at the edge of the arena, where various body-strengthening techniques were stored—though only yamen personnel were allowed to study them.
Upon opening the doors, a musty, moldy odor from damp books assaulted his nose.
He couldn’t help coughing, drawing annoyed glances from those inside.
Looking around, Ren Qing felt a bit disappointed by the so-called martial manuals—it didn’t look any different from an ordinary bookstore.
Three sparse rows of bookshelves held extremely old, even partially damaged books.
He casually picked one up—Breezewind Saber Technique was written on the cover.
Flipping through a few pages, he could only describe it as ordinary. It detailed techniques thoroughly, but it wasn’t the kind of internal-external cultivation art he had expected.
With little hope, Ren Qing summoned the information stream—and to his surprise, it responded.
Breezewind Sword Technique (Incomplete)
Created by Daoist Qingfeng, consisting of 36 forms, known for its speed and stability. With internal cultivation, the swordplay becomes more agile.
Lacks the internal cultivation chapter; cannot consume lifespan to master.
Ren Qing's muscles tensed slightly. Unconvinced, he picked up more manuals—yet all gave similar results.
Every martial manual in the tower was marked as "incomplete." Had the yamen deliberately removed parts of the techniques?
Ren Qing narrowed his eyes, pondering the implications.
There was a vast difference in style between martial arts and sorcery. Logically, wouldn’t widely taught practices be those that enhanced health and strength?
Claiming eerie arts led to immortality didn’t quite add up either.
Even someone like Song Zongwu had a maximum lifespan of only a bit over 300 years. Considering the risks involved, the lifespan gained was minimal.
And how many practitioners truly died of old age?
Ren Qing rubbed his temples in frustration. He felt as though he had accidentally stumbled upon a disturbing truth of this world...
Yet he still had no clue what it was.
Calming his mind, he reasoned that this wasn’t what Song Zongwu wanted him to see—especially since the existence of the information stream was a secret known to no one else.
Ren Qing began patiently flipping through each manual in order, putting them back once the information stream had revealed its contents.
His strange behavior increasingly annoyed the other constables in the room.
Just as someone was about to come warn him, Ren Qing picked up a thick book and quietly sat in a corner to read.
The book was titled Travel Notes from the Grass Hall, and contained absurd tales of gods and ghosts, though the writing was somewhat dull.
After searching through the room, this was the only book that wasn’t a martial manual.
He carefully read every line, and before he knew it, several hours had passed.
As the evening sun shone in through the window, Ren Qing finally looked up, a rare trace of surprise on his calm face.
Around page one hundred, the Grass Hall Travel Notes suddenly shifted tone, beginning to use mythological allegory to hint at the nature of eerie forces and cultivators.
From it, Ren Qing learned the stages of cultivation: Martial Man, Half-Corpse, Ghost Envoy, Yin Messenger, Yang Spirit, and Heavenly Eerie.
As someone who had grasped a sorcery technique and whose body was beginning to change but had not yet transcended mortality, he was currently at the "Martial Man" stage.
Upon undergoing the first transformation, one would reach the "Half-Corpse" stage.
Furthermore, different arts led to very different forms of transformation.
Just the Eyeless Method alone had three branches: "Hundred-Eyed," "One-Eyed," and "Dual-Pupiled"—let alone other arts.
The book also answered a question that had puzzled Ren Qing for a long time:
"To cultivate eerie techniques requires tremendous cost. With such high thresholds, is there no shortcut?"
In fact, there was—and it lay in the bodies of those at the Martial Man stage.
After death, cultivators would produce eerie objects. Ordinary people could master techniques by using them.
However, this only applied to eerie objects from Martial Man stage deaths. Above Half-Corpse, using them became highly dangerous.
For example, a Martial Man who practiced the Eyeless Method would, upon death, leave behind eyes that turned into eerie objects—consuming them would save forty-nine days of cultivation.
But such a person could never advance further, having to rely on eerie items from higher stages, meaning they had no potential left.
By contrast, self-cultivated arts had no such limitation.
What shocked Ren Qing most was that the Forbidden Zones were directly tied to these eerie objects.
When a Half-Corpse or higher dies, the eerie object may gain sentience and roam within a set area—thus forming a Forbidden Zone.
Ren Qing instinctively touched his eyes, feeling a chill creep up his spine.
So that prison Forbidden Zone... was likely caused by a cultivator who died after practicing the Skin Book.
Wait a minute.
If the severity of a Forbidden Zone depended on the cultivator's level... and someone at a high level had mastered multiple eerie techniques... just how terrifying would the resulting Forbidden Zone be?
It was unimaginable.
Ren Qing finally understood why Song Zongwu had chosen to guide him this way.
The transformation he had displayed in prison was linked to the Skin Book. Song Zongwu had mistakenly believed Ren Qing had accidentally consumed a piece of skin and entered the Martial Man stage.
From that perspective, Ren Qing was a low-potential cultivator nearing the end of his lifespan, relying on eerie objects to attain power.
There would be no point recruiting him into the Forbidden Enforcement Squad.
Song Zongwu had already done him a great kindness—preventing him from accidentally revealing his true cultivation and drawing the wrong kind of attention.