Mr. Mu's reply arrived sooner than expected. It was delivered to Ling Zhang on the morning of the third day. At this time the army of the Great Wen had fully taken over the city they had captured a few days ago. Also, troops regroupment had finished, and all units were ready to resume their northward advance.

Ling Zhang and Yuwen Tong had not seen each other for two days. Both of them found the separation unbearably torturous, but Ling Zhang was aware that Yuwen Tong was deeper in misery than he was, because the very thought of him brought Yuwen Tong great pain.

The letter from Mr. Mu was virtually a lifesaver. Ling Zhang, almost bursting with eagerness, quickly opened the bamboo tube and tipped out the letter to read it.

In the letter, Mr. Mu made a very concise reply, saying that that kind of Gu worms were very rare, that the art of raising them had almost been lost to the world. They fed on the affections of their hosts. They had originally been used by Gu masters living in South Xinjiang to punish unfaithful lovers. With that kind of Gu worms inside their body, an unfaithful lover would suffer unendurable pain in the heart every time they thought of the one they had transferred their affections to; the more they missed their new lover, the greater the pain; in some cases, the pain could be severe enough to take the victim's life.

In addition, the more often the victim missed their lover, the faster the Gu worms grew. Normally, they would stay in their hosts' bodies for a month before mauling their hosts to death. The longer they lived in the hosts' bodies, the harder it would be to extract them. Even in South Xinjiang, this kind of worms were very unpopular. In the last imperial dynasty, some people had been employed in raising them, but over time Gu masters with the expertise in raising them had dwindled, and hardly anybody had heard of this kind of worms in the past two centuries.

In the letter, Mr. Mu said that there was a way to lure the worms out, but he had to do it personally; however, given that the worms had been in Yuwen Tong's body for several days, and that Yuwen Tong had deep affection for Ling Zhang, the worms had probably grown up already, and if they stayed in there for another few days, it would be very difficult to extract them, so Mr. Mu told Ling Zhang to use his blood to entice the worms from Yuwen Tong's body.

Ling Zhang's blood, apart from a deterrent to Gu worms, could also serve as a temptation to them. He could use his blood to lure the worms out, but there was a problem: the worms inside Yuwen Tong were a kind of Mother-Child Dyadic Gu. If the method worked, the Child Worm would be lured out first, and what with some kind of telepathic bond shared by the Child Worm and the Mother Worm, once the former sensed danger, the latter would start biting Yuwen Tong's insides instead of coming out. Therefore, Ling Zhang would have to let the Child Worm enter his body after enticing it out of Yuwen Tong's, and that was the only way to lure the Mother Worm out and kill it. As regards the Child Worm, the Force of Blood inside Ling Zhang would restrain it until Mr. Mu arrived and extracted it.

Mr. Mu also specially mentioned that there was also a kind of telepathic bond between the worms and their raiser, who would suffer harm at the death of the Mother Worm and thus came to know about it.

Ling Zhang let out a long sigh of relief at the knowledge that there was a way to lure the worms out. As regards whether or not letting the worm enter his body would put him in any danger, he didn't really care. Besides, he had an advantage over Yuwen Tong – his blood could dampen the activity of the worm.

Having come to know about this method, Ling Zhang couldn't wait to entice the worms from Yuwen Tong's body.

When he had walked through the door, he came to a halt, thought for a moment, then returned inside, took something and walked out again before making towards Yuwen Tong's tent.

Yuwen Tong had not been in a good mood over the last few days. His face further hardened when Ling Zhang, a few moments after a guard outside the tent announced his arrival, still hadn't entered. Since when had Ling Zhang taken to having a guard announce his arrival before entering? But at the thought that maybe the reason why Ling Zhang had come here on his own initiative was because he had received a reply from Mr. Mu, Yuwen Tong couldn't bring himself to be mad at Ling Zhang. He said to the officers who had come to his tent to have a meeting about breaking camp to depart, "I'm afraid I need some privacy. We'll resume the meeting later."

The officers took their leave. When exiting the tent, they caught sight of Ling Zhang waiting outside and hastened to pay their respects to him, baffled as to why the empress was waiting. The marriage between the imperial couple had always been strong. Seldom had the two of them stood on ceremony like this, and Ling Zhang had hardly waited for the emperor to give him permission to enter. When had Ling Zhang ever waited instead of directly going inside?

On top of that, in the past few days the atmosphere between the two of them had been fairly unusual. The emperor seemed to be in a bad mood, and the empress had scarcely left his tent.

The couple of generals couldn't help but wonder whether the two of them had had a fight.

Ling Zhang, unaware that these people had started making speculations so soon, gave them a nod of acknowledgement and then continued waiting for Yuwen Tong to get ready and ask him to enter.

They hadn't seen each other for two days, and Ling Zhang was very worried that a meeting like this might cause Yuwen Tong wide mood swings again.

"Get in here already. What are you standing there for?" Yuwen Tong's voice came from inside the tent, sounding fairly unhappy.

Ling Zhang tightened his hold on what was in his hand and then entered the tent.

At the sight of him, Yuwen Tong's hands balled tightly into fists, blue veins standing out on their backs. He didn't say anything else, staring fixedly at Ling Zhang, a manifestly injured look in his eyes.

Ling Zhang also felt rather upset as he saw this, but this time around he was here to help rid Yuwen Tong's body of the Gu worms, so delight soon took over. "I got a reply from Mr. Mu. There is a way to get rid of the worms."

Astonished, Yuwen Tong sat bolt upright. "Really?"

Ling Zhang said, "Of course. Why else would I come here? The Gu worms will be extracted in a few moments and then you'll be okay."

Yuwen Tong felt a sense of relief which was followed by a sneaking suspicion. "What kind of Gu worms are they? How are you going to get rid of them? And where's Mr. Mu's letter?" he asked.

Ling Zhang said, "I left the letter in my tent. Mr. Mu says that the worms feed on people's affections, that they're very rare."

Then he related to Yuwen Tong what Mr. Mu told him about the worms in the letter, but he skipped the explanation of Mother-Child Dyadic Gu for fear that Yuwen Tong would disagree if he told him he was going to lure one of the worms into his own body instead.

"It never crossed my mind my blood had a function of this kind. I would've spared you the pains you suffered in the past few days had I come to know about it sooner."

Yuwen Tong was also surprised that the problem was so easy to settle, but he still knitted his brows as he heard that Ling Zhang had to use his own blood to entice the worms.

"Let's go inside right now and get it over with," added Ling Zhang immediately for fear of Yuwen Tong becoming suspicious.

"Wait a moment," Yuwen Feng suddenly said.

Ling Zhang affected an air of puzzlement, secretly scared, wondering if Yuwen Tong had found out something.

"Get Xie Shi here and let him handle it. He dresses wounds quicker," Yuwen Tong explained.

Ling Zhang inwardly let out a sigh of relief. "Okay. I forgot about him out of anxiety."

Soon Xie Shi was summoned to the tent. Ling Zhang's method of extracting the Gu worms came as a very pleasant surprise to him, but after a moment he asked in confusion, "Since the worms could be lured out by blood, it doesn't necessarily have to be Your Highness's blood, right? I'll do it."

Xie Shi and the others were unaware of the secret about Ling Zhang's blood.

Yuwen Tong and Ling Zhang knew about it, the former's face faintly sulky. Yuwen Tong was rather unhappy about Ling Zhang having to use his own blood. At the thought that it was all because of the culprit who had put the Gu worms inside him, anger instantly rose inside him.

Ling Zhang shook his head and said to Xie Shi, "That won't work. I can lure out the worms with my blood because I once consumed a kind of special medicinal herb appealing to Gu worms. You've never ingested anything like that, so your blood has no allure for the worms. It's no big deal. I can handle it. All you have to do is dress our wounds as quick as you can after the job is done. It'll be just a minor injury compared with the harm the worms could cause."

Though still somewhat bewildered, Xie Shi, seeing that Yuwen Tong raised no objections, believed that the medicinal herb Ling Zhang had consumed must be very rare. Since neither of his masters showed any inclination to explain in detail, he didn't persist with his questioning and just said, "All right. I'll do what I can to help. I'm pretty good at this kind of stuff."

Ling Zhang inclined his head in a bluff manner. "Okay."

As Ling Zhang had been behaving very normally all along, Yuwen Tong didn't suspect anything. After Xie Shi got the bandages and styptic vulneraries ready, they all went into the inner compartment.

"Lie down on the bed. I'll give you a pill the same as the one you took the other day. We'll start after you fall asleep," Ling Zhang said to Yuwen Tong.

Yuwen Tong objected subconsciously, "What do I have to be asleep?"

With a serious look on his face, Ling Zhang explained, "Mr. Mu said we need to have the worms relax. If you stay awake, the worms would be active and might be unwilling to leave your body. Your body is now rather tense. What if the worms refuse to come out? Surely you don't want us to bleed out?"

Yuwen Tong wrinkled his brow at the last remark of Ling Zhang's. He didn't want to be asleep, but there was too much truth in Ling Zhang's words to ignore them. Most importantly, how could he bring himself to let Ling Zhang's wound keep bleeding?

Xie Shi, listening on the side, became somewhat suspicious. If it was the active ingredient of some kind of herb that was supposed to lure the worms out, Ling Zhang could just put some of his blood in a container to do it. He didn't really have to leave his wound bleeding during the whole process. However, the first half of Ling Zhang's words made sense. The Gu worms would indeed be active if the emperor's body was tense. It would be best if the emperor was put to sleep, because in that case the Gu worms would relax and stop being dependent on his body. As this thought crossed his mind, Xie Shi said, "His Highness has a point. You may rest assured that I'll be cautious, Sire."

Yuwen Tong was not an unreasonable person. Though reluctant, he still took the pill Ling Zhang gave him and lay down on the bed in the knowledge that him being asleep would make it easier for them to lure out the worms.

Before long, he drifted off.

Ling Zhang tentatively called Yuwen Tong's name and then felt Yuwen Tong's pulse. Having checked that Yuwen Tong had indeed fallen asleep, he undid Yuwen Tong's robes, revealing his chest.

Then he rolled up his sleeve, leaving his white-skinned wrist showing.

"Do it."

Xie Shi nodded, carefully produced a sharp, thin dagger, disinfected it with a kind of decoction, lightly cut Yuwen Tong's chest and then Ling Zhang's wrist.

Blood flowed from the cuts.

As Ling Zhang's blood trickled to Yuwen Tong's chest, the tip of Xie Shi's nose twitched. He was not sure whether it was an illusion or not, but it struck him that Ling Zhang's blood did seem to give off a kind of unusual smell. It was some kind of indescribable aroma which almost disguised the foul smell of blood.

"Allow me to bandage that cut for you first, Your Highness," offered Xie Shi hastily as he saw that Ling Zhang had lost a considerable amount of blood.

Ling Zhang, however, was still eyeing Yuwen Tong's wound unblinkingly, his face quite tense. "No," he said.

Xie Shi was amazed. Why?

Right at this moment, something started wriggling beneath the skin around Yuwen Tong's cut. Xie Shi, whose attention was instantly arrested, watched with bated breath.

Ling Zhang's eyes lit up. It really worked! Mr. Mu was definitely worthy of his reputation as a miracle-working physician!

Very soon, a thin transparent worm crawled out of Yuwen Tong's wound. At the sight of the Gu worm, Ling Zhang immediately held his breath, not daring move an inch, allowing his cut to continue bleeding.

Xie Shi, however, raised his hand with the intention to stick a silver needle into the worm to kill it.

Ling Zhang grabbed Xie Shi's arm with his other hand. "Wait. We can't kill it yet."

They couldn't kill it yet? Why? Once again Xie Shi was astonished. He would be a terrible physician if he still hadn't realized there was something out of the ordinary about this matter. "What are you trying to do, Your Highness?"

"I'll explain later. Just do as I say, or else all our efforts will come to nought. Do not bandage my wound unless I tell you to," said Ling Zhang.

Xie Shi didn't dare do anything rash, but he was still somewhat anxious. Of course he was not worried about the possibility of Ling Zhang harming Yuwen Tong, because Ling Zhang was the last person who had a reason to do something like that. However, what did concern him was that Ling Zhang might risk harming himself. How was he supposed to justify himself to Yuwen Tong if something happened to Ling Zhang?

The thin transparent worm was crawling towards the cut in Ling Zhang's wrist so quickly as though it smelled something extremely tempting.

The sight of this made Xie Shi's flesh creep. "You want it to burrow into your body? No, you must not do that! Sire would never agree!"

Looking at the worm with icy eyes, Ling Zhang said, "Calm down. I know what I'm doing. I never joke about my own life."

Xie Shi found himself unable to watch it happen and do nothing. As the worm reached the cut in Ling Zhang's wrist, he raised his needle and was just about to stab it to death when Ling Zhang rapidly immobilized him by hitting a couple of acupoints of Xie Shi's with his finger.

"Your Highness! You must not do this!"

"Shh!"

Ling Zhang gestured for him to keep quiet, watching the worm burrow its way into the cut in his wrist. What with the tingling, itching sensation of numbness in that instant, a thin layer of fine beads of sweat broke out over his back, but he still stayed quite motionless, because he knew that the Mother Worm was still in there, and in no circumstances should he let anything happen to the Child Worm. He must endure the pain and allow the Child Worm to go deeper into his body.

Xie Shi was so anxious his face was beaded with perspiration. However, he was unable to unblock the acupoints hit by Ling Zhang with his internal energy no matter how hard he tried. Right at the time when his anxiety began to blind him, he suddenly heard Ling Zhang say, "Here it is."

Xie Shi was astonished. Only then did he notice that there was actually something else wriggling beneath Yuwen Tong's skin around the cut in his chest. After a few moments, a bigger, also transparent worm came emerging from the wound. He was astounded to such an extent that he seemed to forget why he had been anxious all this time. "Wh–What's going on?"

Ling Zhang unblocked Xie Shi's acupoints and hissed, "Kill it. Hurry!"

No sooner had Xie Shi regained his ability to move than he impaled the Gu worm on his needle, put it into a porcelain bowl containing a highly corrosive substance and with that the worm instantly started writhing madly. Before long, its whole body was dissolved completely.

With a muffled groan, Ling Zhang's face suddenly changed, droplets of sweat instantaneously welling up on his forehead. Presumably having sensed the death of the Mother Worm, the Child Worm which had wormed its way into his body began to gnaw his flesh frantically. The pain that had spread all over his body in a flash caught Ling Zhang flat-footed. It was an agony the likes of which he had never experienced before, and which felt as though someone were scratching his insides with a knife.

"Your Highness!" Xie Shi was taken aback.

Ling Zhang shook his head at Xie Shi, produced a pill and put it into his mouth. The pill melted as it went down his throat. Soon the pill took effect, its active ingredient beginning to permeate his whole body. The activity of the Gu worm mauling his insides seemed to be dampened, his pain deadened somewhat.

It was his grandfather who had given the pill to him. The pill was meant to help him make a breakthrough in his cultivation of internal energy. It could enhance the Force of Blood in him, making it easier for him to reach the seventh layer. He was not ready to make a breakthrough yet, but the pill served another purpose. The idea had come to him in a flash of inspiration and he had decided to give it a shot. It surprised him that it was really working. Not daring take any more risks, he hastened to sit cross-legged, preparing to circulate his Chi. Meanwhile, he said to Xie Shi, "Dress our cuts."

It was only then that Xie Shi came to himself as though waking up from a dream. He quickly applied some styptic drug to that rather ghastly wound of Ling Zhang's before scrupulously bandaging it, opening and closing his mouth repeatedly as if having something to say.

"I'll answer your questions after I finish my Chi circulation," said Ling Zhang.

Xie Shi pressed his lips together and inclined his head. After dressing Ling Zhang's cut, he hastened to bandage Yuwen Tong's.

"There's no Gu worm in Sire's body now, right?" said Xie Shi. It had come as a great surprise to him that there had been two worms inside Yuwen Tong's body.

"No. There were two worms in total. They're a kind of Mother-Child Dyadic Gu," replied Ling Zhang, closing his eyes as Xie Shi finished bandaging the cut in Yuwen Tong's chest.

Seeing this, Xie Shi didn't dare ask any more questions. However, at the thought that there was still a Gu worm in Ling Zhang's body, he wrinkled his brow in worry, at a loss what to do.

As Ling Zhang's Chi started circulating, his pain gradually eased. He speculated that Mr. Mu probably didn't know the Child Worm would react so violently to the death of the Mother Worm either, but no matter what, he could relax safe in the knowledge that Yuwen Tong's body had now been rid of Gu worms.

Gradually, Ling Zhang entered a state of meditation.

Silence reigned over the main tent.

Meanwhile, in a room in Jifang City, the countenance of the old gray-robed man, who was sitting beside Chen Jing as his savior having a meeting about the plan for defending the city, abruptly changed. After a few moments, his face turned purple and with that he spat out a mouthful of blood.

"Master?!" Chen Jing was startled.