Sect Master Position
Cao Xiong competed with Su Yonghuang for the Sect Master position, but failed. Even so, he still wanted it badly, if not for himself, then at least for his disciple, Leng Shizhi. Thus Cao Xiong repeatedly proposed to make Leng Shizhi the Prime Disciple, but was constantly rejected by Su Yonghuang.
Accepting the Prime Disciple
When Li Qiye came to the Cleansing Incense Ancient Sect with the Third Ancient Order and asked for the position of the Prime Disciple, Cao Xiong urged the rest of the Elders to agree with Li Qiye's request, at least in order to return the Third Ancient Order back to the Sect.
However, his true intentions were to allow useless mortal to become the Prime Disciple, so that the Sect Master and other Elders had no choice but to choose Cao Xiong's disciple, Leng Shizhi, as the next Sect Master.
Li Qiye's Return
After Li Qiye returned to the Cleansing Incense Ancient Sect from the Nine Saint Demon Gate, the Elders was shocked to hear what he has successfully passed all trials of the Ancient Marriage Treaty. Cao Xiong, however, was greatly alarmed, because Li Qiye's success means that he could marry Li Shuangyan. If Li Qiye could obtain the support of the Nine Saint Demon Gate, then nor Cao Xiong nor Leng Shizhi will have any chance to become the Sect Master.
In this regard, Cao Xiong became very antagonistic towards Li Qiye and tried to accuse him of being the Nine Saint Demon Gate's spy. But Elder Sun disagreed and argued, that the Gate was currently many times stronger than the Cleansing Incense Ancient Sect and basically didn't have any need to send spies as they can easily destroy the Sect if they wanted.
Li Shuangyan's visit
To their surprise, it wasn't only Li Shuangyan who came; she was accompanied by Grand Protector Yu He. They were even more surprised by Yu He's extremerly polite attitude towards Li Qiye. On behalf of the Demon King, Yu He invited Li Qiye to visit the Nine Saint Demon Gate in his spare time and assured him that the Demon King will personally meet him. Li Qiye thanked Yu He, and told him to feel at home in the Sect, and if there are any inconveniences, to just let Protector Mo or Nan Huairen know. After that Li Qiye went away with Li Shuangyan under the gazes of the shocked crowd.
When First Elder decided that Li Qiye will temporarily became instructor of newly disciples at the Strange Gem Peak. However, Cao Xiong intervened and Li Qiye was appointed to the Cleansing Jade Peak, where Cao Xiong has great influence, because his disciple, Leng Shizhi, also studied there.
Several days later Gu Tieshou had gathered the other Elders to discuss the King Physique Paste what they promised to Li Qiye. He also notified them that Li Qiye requires the Hell Iron Bull's marrow as the leading component of the Paste and how much is a cost for it. Elder Qian, Elder Zhou and Elder Wu weren't happy to pay so much. Cao Xiong tried to play on their displeasure and convince them to cancel the deal altogether. He hoped to use the Sect's last King Physique Paste for his own disciple, Leng Shizhi. Eventually, Gu Tieshou used his aura to supress them all and forced them to agree.
Half a year later Li Qiye reached the peak of the Physique Accumulation's second stage. He required the Physique Paste to enter the Physique Accumulation's third stage, so he went to First Elder for the Physique Paste that Six Elders promised to him.
First Elder already gathered all materials needed and was only unsure on how to refine the Paste. The Cleansing Incense Ancient Sect had two Alchemists who were capable to create a King Physique Paste: Cao Xiong and Elder Sun. Elder Sun was ready to help, but wasn't too sure in the result. Cao Xiong, on the other hand, was sure in result, but wasn't willing to help. Li Qiye thus decided that he would take care about Paste's creation himself.
Massacre at the Cleansing Jade Peak
Unable to do anything to Li Shuangyan, and, seeing how close she became with Li Qiye, Cao Xiong was greatly alarmed. He always wanted to become a Sect Master, or at least to push Leng Shizhi into this position, but Li Qiye's potential marriage with Li Shuangyan ruined all of his plans and dreams. Cao Xiong went to a meeting with Dong Shenglong, who promised to him the Heavenly Jewel Kingdom's support. Together they planned to frame Li Qiye in some major crime and then use the Sect rules to demote or maybe even kill him. Without Li Qiye, they then would push Leng Shizhi into position of the Prime Disciple, and then Sect Master.
Few days later Cao Xiong sent Sectional Leader Zhou to cause trouble at the Cleansing Jade Peak to provoke Li Qiye. Li Qiye defeated Sectional Leader Zhou, but Zhou summoned a law enforcement team that "coincidentally" patrolled nearby. This law enforcement team was formed from the Cao Xiong's supporters and was led by his disciples, Protector Hu and Leng Shizhi. They immediately framed Li Qiye in many crimes and used it as an excuse to attack him. Li Qiye, however, easily killed them all.
Soon after Gu Tieshou and other Elders also arrived and demanded an explanation. Cao Xiong blamed Li Qiye in betraying the Sect and killing his fellow disciples and the law enforcement team. Li Qiye retorted that the traitor was not he, but rather Cao Xiong, who conspired with Dong Shenglong to frame and kill him in order to destroy the marital agreement between the Cleansing Incense Ancient Sect and the Nine Saint Demon Gate, because it would threaten Dong Shenglong's Heavenly God Sect.
Abandoned by Dong Shenglong, Cao Xiong still tried to incriminate Li Qiye. His follower Sectional Leader Zhou accused Li Qiye in teaching wrong merit laws to the Cleansing Jade Peak's disciples and undermining their cultivation. Gu Tieshou then asked several disciples about Li Qiye's teachings. He and other Elders were shocked by Li Qiye's knowleadge and insights, and reprimanded Sectional Leader Zhou for his wrong judgement. Cao Xiong was frustrated by this development, but even he was marveled by Li Qiye's knowleadge and could not find any flaws in his teachings.
New Hope for the Sect
Cao Xiong then used his last ace and accused Li Qiye in stealing the manual for Kun Peng's Six Variants. As the Sect's last complete Immortal Emperor Merit Law, the Kun Peng's Six Variants was heavily guarded, and even Elders could not easily get access to it. Li Qiye, however, told them that after learning the Kun Peng's Six Minor Forms he saw an "old grandpa" in his dream and learned the Kun Peng's Six Variants from him.
While not fully believing him, the Elders decided to give it a try and allowed Li Qiye to study another Minor Emperor Merit Law, the Violet Cloud Merit Law, in the hope that "old grandpa" will taught him its superior form. Three months later Li Qiye successfully brought the complete manual for the Violet Yang Ten Suns Merit Law.
As a reward for his great merits, Li Qiye asked the Elders to allow Protector Mo and Nan Huairen to learn the Violet Yang Ten Suns Merit Law. Cao Xiong was against it, but other Elders agreed.
Because of Li Qiye's achievements and potential, five Elders decided to wave off his crimes. Cao Xiong, however, insisted that they need to punish him at least a little to appease other diciples. The Elders then decided to send Li Qiye to the Ghost Pavilion for half a year with Protector Mo as overseer.
Since entire situation was caused by Sectional Leader Zhou, Gu Tieshou ordered to take away his position. Sectional Leader Zhou was one of his last loyal followers, however, at this moment, Cao Xiong had no choice but to acquiesce and support Gu Tieshou's decision.
Heavenly Jewel Kingdom's attack
After the official meeting, Cao Xiong was secretly meeting with Dong Shenglong. Dong Shenglong promised to him that as long as Cao Xiong deliver Min Ren's Heaven's Will Secret Law to the Heavenly Jewel Kingdom, they would help him to become the Cleansing Incense Ancient Sect's next Sect Master and wouldn't bother the Sect anymore and Cao Xiong agreed. Dong Shenglong then contacted the Heavenly Jewel Kingdom and they sent War Noble Lie with an army to attack the Cleansing Incense Ancient Sect.
When War Noble Lie arrived with an army in the Cleansing Incense Ancient Sect, he chalenged Gu Tieshou for a "sparring match". Cao Xiong interfered and tried to teach War Noble Lie a lesson, but was quickly defeated and seemingly injured. Gu Tieshou then ordered the other elders to escort Cao Xiong back into the Sect and heal his wounds. In truth, however, their battle was just for show so that Cao Xiong had an excuse to return to the Sect and get Min Ren's Heaven's Will Secret Law, while everyone's attention was directed at invassion.
Five days later Cao Xiong came to the Zither Pavilion with a copy of Daylight Sky Merit Law's manual. He urged Li Qiye to study it in the hope that he could obtain Min Ren's Heaven's Will Secret Law, ostensibly to help Gu Tieshou in his battle. Li Qiye, however, easily deduced his real intentions and refused to cooperate. At this moment, Protector Mo, who had watched over Cao Xiong in recent days, brought other elders into the Zither Pavilion. All of them witnessed Cao Xiong's betrayal and demanded him to surrender. Cao Xiong then captured Li Qiye and threatened to kill him if other didn't make way. Before anyone could react, Dong Shenglong also came into the Zither Pavilion.
After learning how to obtain Min Ren's Heaven's Will Secret Law, Dong Shenglong decided to kill elders and push the blame on Li Shuangyan and Nine Saint Demon Gate, but, before he could do anything, Li Qiye activated Zither Pavilion and killed Cao Xiong.