Humanity's strength has its limits, and Open Heaven has its shackles.
How high a cultivator in the Open Heaven Realm could climb the summit of martial cultivation, and what kind of achievements they could ultimately attain, was all determined by their starting point when they broke through to Open Heaven.
Generally speaking, after breaking through to Open Heaven, no matter how hard one cultivated, one could at most advance another two grades further.
This was also why the Cave Heavens and Blessed Lands invested so heavily in nurturing elite disciples—only those who broke through directly to Fifth Grade or above had any hope of achieving Upper-Grade Open Heaven in the future.
Breaking through directly to Fourth Grade meant one's limit was merely Sixth Grade at best.
But the Ink Force, after corrupting those in the Open Heaven Realm, could shatter this ceiling, allowing Open Heaven cultivators to advance without limit.
For any Open Heaven cultivator, this was an indescribable temptation.
Even Yuan Du, the Vice Temple Master of the Langya Blessed Lands, had been unable to resist such temptation. He had actively sought out the Ink Force, ultimately falling into servitude as an Ink Slave and sowing chaos within Langya.
One could well imagine the shockwaves such news would send through the Three Thousand Worlds. Yuan Du was far from the only one out there whose martial path had been stymied by insurmountable bottlenecks.
However, the world only knew half the truth. While the Ink Force could indeed help Open Heaven cultivators shatter their shackles and achieve things impossible through ordinary means, doing so required a price—and that price was often unbearable.
Back in the Black Prison, Yang Kai had personally witnessed several Open Heaven cultivators use the Ink Force to break through their own limitations.
But the fates of those individuals had been no less grim.
Breaking through the barriers and experiencing a violent surge in power could either cause one's body to explode and perish, destroying both life and Dao, or it could drastically alter one's physical form, turning one into something monstrous, causing one to lose one's true nature and become consumed by brutality.
The Ink Slave who had suddenly appeared before him was undoubtedly the latter case.
The fleshy tumor on his neck, the hump on his back, and even his inhumanly massive frame—all were clearly the result of Ink Force corruption.
In other words, this person could never have possessed Seventh Grade Open Heaven cultivation on his own. But with the help of the Ink Force, he had pushed past his natural limits. While he had gained a higher grade, his body had also undergone several grotesque transformations.
Yang Kai could sense it clearly—the aura of this Seventh Grade cultivator, while fierce and vicious, was fundamentally unstable, like a building riddled with termites that could topple at the slightest push.
If he continued cultivating, as his strength grew, the likelihood of his body exploding under power it could not contain would only increase.
For someone like him, even if the Purifying Light was used to drive the Ink Force from his body, there would be no saving him. His Small Universe could only withstand Sixth Grade power—Seventh Grade Open Heaven strength had already exceeded his limits. Once the Ink Force was removed, without its support, he would fall in an instant.
A cascade of thoughts flashed through Yang Kai's mind like lightning. With a quiet sigh in his heart, Yang Kai asked, "And you are...?"
The newcomer cupped his fists and grinned broadly. "Liu Zi'an, an Ink Slave under Lord Gui Liao."
"So it's Brother Liu!" Yang Kai nodded slightly. "Is there something you need?"
Liu Zi'an laughed heartily. "I heard that the Domain Lord personally took in an Ink Slave, and out of curiosity, I came to see for myself. Our Domain Lord is incredibly powerful—he doesn't usually think much of ordinary Ink Slaves. In all these years, I've never seen him personally accept one. Brother Yang, you're the first."
"That's quite the honor!" Yang Kai replied modestly. Noticing that Liu Zi'an likely had something to discuss, he stepped aside and said, "Come inside, Brother Liu. Let's talk."
Liu Zi'an didn't stand on ceremony, either. He strode inside in large steps.
Yang Kai shut the door. The side hall had been completely empty — no one had lived here for a long time. Since Yang Kai had only just arrived, he hadn't prepared anything, so he produced a set of table and chairs from his Small Cosmos and arranged them, gesturing for his guest to sit.
Liu Zi'an dropped into a seat without any pretense.
Yang Kai sat down as well and spoke up. "Brother Liu, you mentioned earlier that you're an Ink Slave under Lord Guiyao's command?"
"That's right." Liu Zi'an nodded.
"How long have you been here, Brother Liu?" Yang Kai asked.
Liu Zi'an smacked his lips and said with a sigh, "Quite a while — roughly a thousand years."
"That is indeed a long time." Yang Kai gave a slight nod. "I've only just arrived and know virtually nothing about the Ink Clan's affairs. I'll be counting on you to show me the ropes going forward, Brother Liu."
Liu Zi'an laughed heartily. "Say no more, say no more — we both serve under the Domain Lord. If there's anything I can help with, just call on me anytime. Even though we're Ink Slaves, we still come from the same race, after all. It's only proper that we grow close."
"Well said, Brother Liu." Yang Kai nodded in eager agreement. "I wonder — which Blessed Land or Cave Heaven did Brother Liu originally come from?"
Liu Zi'an waved a dismissive hand. "Once you've become an Ink Slave, the past has nothing to do with you anymore. No need to bring up old origins. Since you've come to the Ink Clan's side, you should follow local customs."
"Understood." Yang Kai adopted a chastened expression.
Liu Zi'an went on. "To tell the truth, when I first arrived among the Ink Clan, I was incredibly out of place. But once I'd spent enough time here, I realized it's really no different from the Human Race's side — it's all about social connections. If you want someone to do something for you, or to be taken seriously, all you have to do is build good relationships. Everything else follows naturally."
A sharp glint flashed through Yang Kai's eyes. "Brother Liu, you make an excellent point!"