Seeing Cao Yun in a very bad position, Luduo Bu pressed on with his attacks. He was utterly convinced that his Evil Qi was working perfectly. Technically, it was due to it, but the true culprit of Cao Yun's weakness was the Drop of Wrath.
Within his mind and body, he was circulating an increasing part of his mind to fight off its intent. The Drop of Wrath was actively trying to stir the Evil Qi through Cao Yun's bloodstream toward his heart. The most likely reason was to strengthen itself by absorbing it. A possibility emerged in Cao Yun and he wondered whether this Drop of Wrath came from a demonic cultivator. The fact that it was linked to blood was not proof enough, many orthodox martial arts were linked to blood after all. But if it was trying to feed off Evil Qi, maybe it was evil in nature.
Evil Qi was not just Qi. This was a kind of Qi with extreme Yin properties. And more than that, this was a Qi polluted by resentment. This kind of Qi could appear naturally. For example, after a tragedy some Evil Qi could be formed. This was akin to ghostly energy in a sense. And ghosts were very fond of Evil Qi themselves. Most of the time, Evil Qi was pretty tame as long as there wasn't too much of it. To make it as corrosive as it was now required a great level of resentment.
Luduo Bu had cultivated this Evil Qi by slaughtering human cultivators and absorbing their blood. The way he killed them was brutal and he extracted a lot of Evil Qi from them. His 'Blood Runes' method was even able to amplify Evil Qi by condensing it. One way to refine this Evil Qi was to use one's own resentment. To do so, the easiest way was to harness the resentment of an inner demon. This was what had allowed Luduo Bu to enhance his strength so fast, but it also became his downfall.
Moreover, after the inner demon took over and slaughtered Fulao, the Evil Qi around him had increased exponentially. The cultivators and mortals he had tortured to death in this small city were still being used by him in death. This was a part of their resentment that entered Cao Yun.
In the real world, Luduo Bu kept attacking both with the blood runes and his 'Bloody Cavalry' expressed through his halberd. Each strike was accompanied by thin layers of blood. Despite not being a Mortal Warrior, he was extremely close to it and he was able to send a small part of Qi through this layer of blood. No strange phenomenon got manifested but it turned each slash into a poisonous attack.
Absorbing more Evil Qi would weaken Cao Yun even more. In this case, he would have to focus more of his mind into stopping it and the Drop of Wrath would probably grow even more envious of this energy. As such, an even bigger part of his mind would need to fight it off. In the end, he would have almost no more focus on the actual fight. Thinking about it amidst the fight, the solution finally popped up in Cao Yun's head. The Drop of Wrath was agitated by the Evil Qi in his bloodstream. So if he got rid of it, it would maybe calm down.
With this thought in mind, he almost let go of the Drop of Wrath's intent. All the intent he used within his body got focused on the two surges of Evil Qi. As soon as he let go of the Drop of Wrath's intent, the attraction it exerted on those two surges increased dramatically. However, thanks to his Po character, Cao Yun had a better control over his Qi. Pushing it to the limit, he was able to force the Evil Qi out of his bloodstream. Fighting against both the Evil Qi trying to infiltrate his body and the Drop of Wrath trying to attract it deeper in his heart, at last, he had purged the intruders.
In the physical fight, Cao Yun was in a tight spot. Using his speed, he could dodge the attacks of both the blood runes and Luduo Bu. However, he could not divert any attention to attacking or he would risk being infected with Evil Qi again. For now, the Drop of Wrath had indeed calmed down, but it could become even more violent if other surges of Evil Qi were to penetrate Cao Yun's defenses. But on the other hand, if he did not attack, he would exhaust his strength way sooner than Luduo Bu, considering his cultivation level.
His only hope seemed to be an outside help. The problem was that he had chosen this spot for his Seamless Qi Vortex array formation precisely because no one seemed to pass through here. He had to find a solution himself. Pushing the 'Azure Dragon's Seven Piercing Stars' to its limits, a sudden explosion of white light eclipsed all the stars in his sea of consciousness. The Root Star had reacted. For a while now, Cao Yun had been trying to pierce its secrets and he was ever so close to do so. Immediately, he understood. The principle behind the first move of the Root Star was similar to what he had just done. Using his own Qi to expel a foreign influence could also be used to repel attacks on the outside.
This was 'Dragon's Chest'. By focusing the Qi in specific areas and circulating it in a certain way, he could strengthen his body and resist attacks. If Cao Yun had been a Mortal Warrior, scales of a dragon would have even appeared on the spot he was focusing his Qi. Just knowing the technique was not enough, he also had to test it in real life. Unfortunately, he had no right to fail in an actual battle.
Without any other choice, Cao Yun tried to meditate on this technique while dodging. But Luduo Bu became more and more violent with his attacks, if that was even possible. Finally, Cao Yun who was getting tired got hit by a blood rune in the back. As soon as he understood that he could not dodge this one, he tried out 'Dragon's Chest'.
Contrary to its name, it could be used anywhere on the body. When the blood rune collided with his defense, it got repelled and Cao Yun was not cut. However, he was sent forward by the impact. Thankfully, it wasn't so bad because the blood runes were not too fast yet. Their impact was comparable to what he had suffered during his training in the Thousand Snakes Invade the Shell array formation.
Seeing this, Luduo Bu became enraged and started screaming to death. His best technique had failed to cut Cao Yun. This boy was a nightmare for him. No matter what he did, he always failed faced to this insignificant brat. An inner demon was of course way more vulnerable to mood swings. Luduo Bu changed all his strategy and rushed toward Cao Yun to beat him up in a more personal manner.
Now that the Evil Qi had been purged, Cao Yun diverted all his focus on the fight. Luckily he had been right and the Drop of Wrath was calm for now. However, Cao Yun was terrified by the idea of being overtaken by it again. He really had to end this fight as fast as possible. Up close with Luduo Bu, even with his new understanding of 'Dragon's Chest', the fight was tough. Thanks to both his Po character and his collateral meridians being wider than the norm, he could easily send Qi wherever he needed even faster than his opponent.
However Luduo Bu had the physical strength of a 1st-grade Mortal Warrior. Even without the ability to manifest Qi, this was a tremendous strength. No matter how much Qi Cao Yun used, he was pushed back with every strike blocked. Cao Yun even used all the techniques of 'Dance of Slaughter'. In fact, he got forced to integrate the concept of vibration from 'Slaughtering the Enemy' to the 'Dragon's Chest. This technique even served to strengthen his grip of his spear. Otherwise, his hands would have been destroyed by the impact the first time he had dodged Luduo Bu's physical halberd.
Finally, Cao Yun was sent flying by a powerful strike to his lower abdomen. He fell into the basin, right before Huang Cixi's eyes. Still lying down, he saw the girl's shocked face.
"Mei Yuzhi, run!"
The young girl had no time to do or say anything. Luduo Bu was standing on the edge of the basin, looking at her as dead meat.
"Oh? Your little servant is here? Great! I want to see your face when I skin her alive!"
Luduo Bu was even more sadistic and violent now that his inner demon had taken over. Hearing these words, Cao Yun circulated all his Qi and jumped back up.
"You'll have to go through me!" His brave words were met with Luduo Bu's maniac laugh.
Cao Yun was weakened and this threat against his servant was plunging his mind in turmoil. The Drop of Wrath was agitated once more. But this time, Cao Yun had not the luxury to care about this. If he couldn't contain Luduo Bu, Huang Cixi would die very fast. And he even had the strange blood runes. If only one of them went past him, Huang Cixi would die. To avoid that, he needed to use all of his strength and push Luduo Bu back. But even then, he could easily kill his servant. He had to find a way!
Seeing the array formation around him, Cao Yun got an idea. He activated the Seamless Qi Vortex array formation. By doing so, a vortex of pure Qi condensed around Cao Yun and started to replenish his strength. Luduo Bu had no understanding of array formations so he did not understand what was going on. Instinctively, he jumped back. Thanks to his 'Shen Visualization', Cao Yun went through rudimentary array formations and one suddenly popped up in his mind.
He changed the array formation around him and formed the Dark Veil array formation. This array formation was able to hide one's presence. It was a very standard array formation, and very weak. But from what he had witnessed, the blood runes were not intelligent. They seemed to only attack by instinct. So even such a weak array formation would be able to hinder their detection abilities. He had thought about using a defensive array formation but their force was too high even for the strongest array formation he could set up.
"Mei Yuzhi, come inside!" She did not hesitate at all. The young girl knew that her master was talented in array formations. Despite his talent, this array formation was very rudimentary and set up in haste. As such, it did not even reach the Perfect rank, it was only 68% effective. Luckily, he had already a great understanding of this place, so he could set up such a simple array formation in a matter of seconds.
When Luduo Bu understood he had been duped, he charged forward. Cao Yun did the same and rushed him. Using his entire body, launched with his 'The Moon Grounds the Sun', as a battering ram, he pushed Luduo Bu out of the basin. He left two blood runes behind to try and kill Huang Cixi. But he had lost her visual and the blood runes were perturbed by the Dark Veil array formation.
Huang Cixi laid down, flat on the ground. If she were to try and run, the blood runes would easily detect her and she would die immediately. However, the array formation had already used most of the spirit stones. As such, Cao Yun was worried. Time was already his enemy, but now it was also Huang Cixi's enemy.
He decided to throw all cautious to the wind. He pushed his Qi to the limit and attacked relentlessly. After racking his brain, he had failed to find a good way of winning.
Thanks this speed, he was able to avoid all the attacks of his opponent, even at point-blank. As such, he had opted for an harassment strategy. His projected 'Dragon's Twin Horns' could not pierce through Luduo Bu's defense, but his 'The Pillar Piercing the Sky' was different. He could inject his understanding of vibrations into the 'Nine Chi Black Dragon Spear'. Thanks to that, even though his spear could only inflict superficial wounds, its force penetrated deep within the body. Luduo Bu's organs were damaged by each strike. However, using the 'Flowing Blood' from 'Blood Runes', he absorbed three blood runes. Two of them were used to heal and protect his insides while the third one was used to enhance his defense.
Thanks to the very small time Cao Yun had spent in the Seamless Qi Vortex array formation, he had regained a third of the energy already used in the fight. Luckily, he had trained just before so his meridians and vessels were still fully open and could absorb more Qi than usual.
Unfortunately, he wouldn't be able to convert the array formation back during this fight. Thinking about Huang Cixi, he got more and more agitated as the fight went on. Within his sea of consciousness, the Drop of Wrath was also excited. It got extremely agitated but Cao Yun just decided to turn a blind eye to it. If he diverted an ounce of his focus from the fight, he would have no chance to protect his servant. The fight would drag on, the array formation would collapse and she would die.
As long as he took care of Luduo Bu fast enough, he could regain control over the Drop of Wrath.
In his sea of consciousness, the three stars of the 'Azure Dragon's Seven Piercing Stars' shined brighter and brighter. The entire ocean turned almost white as the Root Star shined brighter than all the other stars. Cao Yun had just understood its first move and it seemed elated. The 'Dragon's Chest' allowed him to keep his grip on the spear no matter how powerful the collisions with Luduo Bu's weapon and body were.
Soon, Luduo Bu turned absolutely insane. He kept trying to strike Cao Yun down. Up close, he only needed one hit to kill him but all his attacks were dodged. His frustration built up and strengthened the inner demon's grip on Luduo Bu's body. He was now revolving all his Evil Qi to try and increase his leg muscles and thus his speed.
Even with Cao Yun's understanding of vibrations, his attacks had a minimal effect on Luduo Bu. Paradoxically, the Evil Qi had more effect. Indeed, his organs were starting to be corroded by the Evil Qi itself and were only protected by his 'Flowing Blood' which also sent even more Evil Qi in his system.
As the fight went on, Cao Yun seemed to gain the upper hand. Deep within, the Drop of Wrath was ready to attempt another takeover. His sea of consciousness turned into blood. His mind got forcefully pulled in. Cao Yun resisted but the distraction got him.
A blood rune flew in his back and pierced through his flesh, straight toward his heart.