Sword Trial Assembly
The three sects of Drifting Cloud, Ancient Sword and Hundred Possibilities Pavilion were aware of spies within their ranks. During the Sword Trial Assembly, Elder Cheng Tiankun and Elder Lu Luo led their forces against enemies. They were ambushed by the Heavenly Fiend Sect and the Thousand Illusions Sect though. Cheng Tiankun was heavily injured and his origin Qi was greatly damaged. Despite recovery, his vitality was harmed and he had about 80 years to live out of 200 years left.
Cheng Tiankun was cultivating in his cave residence when he was startled by his spiritual sense. He was in disbelief that someone had been forming their Nascent Soul within the Drifting Cloud Sect. Elder Lu Luo quickly met with him. In their discussion, they deduced that the individual was likely a vagrant cultivator seeking protection within their sect. Adept at diplomacy and administration, they made the choice to befriend the vagrant cultivator.
Shortly after, they met Han Li. They were surprised to learn that Han Li had formed a Nascent Soul with only two centuries of cultivation. Immediately, they knew that they had to recruit Han Li to be an elder of the sect. They offered him guidance and help in cultivation. Three days later, Han Li agreed. Delighted elders introduced him to the Core formation cultivators and gave him a mountain for abode.
Later on, Cheng Tiankun shared the information about his shortened lifespan with Elder Lu Luo. He wanted to really befriend Han Li, so that he could help the sect, when Elder Cheng would be gone. He sent Lu Luo with Han Li and others to the largest trade meet in Soaring Heavens City, while he stayed at the sect.
When Han Li's Dao Companion Nangong Wan appeared in the Drifting Cloud Sect, Cheng Tiankun promptly arranged for her to be protected and secluded. His actions, successfully deepened the relationship between Han Li and the sect. Yin Sifting Sect Elder attacked Nangong Wan and put the Soul Seal Curse on her. Elder Cheng intervened, but the black-robed cultivator escaped. A demand was left, that Han Li was to bring him the treasure refined from Golden Lightning Bamboo. Elder Cheng with several friendly cultivators supported him from distance. After Han Li disappeared in a transportation formation, Cheng Tiankun and others were left behind. Soon, they found a way to Han Li's location, and not long after that reunited with him and then returned to the sect. Han Li informed Elder Cheng about the methods to dispell the Soul Seal Curse he learnt from soul search.
After the Ghost Spirit Sect started sending cultivators into Devilfall Valley, Elder Cheng and two fellow cultivators, that were nearing the end of their lifespans, used their method to entere the valley too. While being inside the valley, one of cultivators lost life. Later, Elder Cheng, his friend, Daoist Heavencrystal, Ling Hu, the Grand Elder of Masked Moon Sect and Han Li joined Wei Wuya, who was fighting an Elder Devil Bloodflame. The original Elder Devil and its soul fragment, that were at odds, turned to devour Nascent Soul cultivators first. Ling Hu, the Grand Elder of Masked Moon Sect and Wei Wuya faced the soul fragment, while Daoist Heavencrystal, Elder Cheng, his friend and Han Li battled the original Bloodflame. His friend's and Daoist Heavencrystal's Nascent Souls were eaten. Han Li managed to trap Bloodflame with the Aureate Sword Formation. When Han Li used Spirit Subjugation Talisman to kill him, spatial tear appeared and sucked both of them. Elder Cheng remained facing newly arrived Bloodflame's soul fragment. Then Dongmen Tu and Ghost Spirit Sect's Elder Zhong appeared. With Elder Devil in furry, the Moulan also arrived. Sage Le summoned the Moulan Sacred Bird and they were able to grievously wound the devil. The Moulan Divine Sage Zhong was able to cut off one of Bloodflame's heads. Cheng Tiankun managed to survive, but he did not find any life-prolonging medicine pills in Devilfall Valley.
Number One Sect
When Han Li returned safely after 27 years, Elder Cheng and Lu Luo were overjoyed. They were even greatly suprised, he reached a mid Nascent Soul stage. In next 2 days, Elder Cheng, Lu Luo and Han Li travelled to the Hundred Possibilities Sect for the master recognition ceremony. A young cultivator was bonding with refined Yin Yang Pagoda. There they met Ancient Sword Sect Elders. Jin Wuhuan was interested in Han Li's abilities. During the ceremony, Master Sunreach visited the Hundred Possibilities Sect to see Han Li. After Jin Wuhuan lost duel to Han Li, the Drifting Cloud Sect became the number one sect in the Dreamcloud Mountains. Elders Cheng and Lu were excited. They wanted to appoint him as the Grand Elder, but Han Li strongly refused, because it would conflict with his goal of cultivation and pursuing Dao.
Some time later, Cheng Tiankun passed away. When Han Li learnt about that later, he was struck by a hint of grief upon hearing about that.