As befitting an avowed pacifist, the special moves of Shang Bu Huan's secret sword techniques are all counters. He did not use Formless Rogue Sword: Eight-Way Arrival until Can Xiong advanced upon him first. Likewise for Formless Rogue Sword: Specter Shattering, which Shang Bu Huan doesn't move and waits for Diao Ming to bring himself into range. Sha Wu Sheng even emphasizes this aspect. He never launched an attack on Shang Bu Huan during their conversation because every scenario he imagined would result in Shang Bu Huan successfully countering his assault.
Sha Wu Sheng dearly wants Lin dead. In the finale, Lin reveals himself as possibly the strongest person in the show, after Shang Bu Huan. Sha Wu Sheng is after Lin not because Lin stole an item from him, but because Lin stole his title and self-assurance in being the strongest swordsman, which Sha Wu Sheng can never get back so long as Lin lives. He isn't trying to kill Lin out of revenge alone, but so that he can retake his title as the strongest warrior in Dong Li.
The movie also shows that Sha Wu Sheng sorely wants Lin Xue Ya dead because Lin stole from him the ability to ever be considered an honorable swordsman by rigging a competition in his favor by getting Shou Yun Xiao to kill most of the other contestants.
Throughout the series, Shang Bu Huan is seen fighting with his fists and feet, an umbrella, a scabbard, and the handle of his sword. Other characters such as the One-Eyed-Impaler and the Frozen Wonder incorporate martial arts, but Shang Bu Huan utilizes tools other than the blade of his sword far more often. There doesn't seem to be a Thou Shalt Not Kill policy in play and he fairly easily kills mooks without a sharp edge. Seems like an extra waste of effort... until you learn that Shang Bu Huan's sword is just a wooden stick painted silver, and, in order to kill with it, he has to undergo the difficult process of channeling chi through it to give it an edge. He has been intentionally handicapping himself in every single fight he's been in in order to make him feel the actual emotional and physical weight of having to kill someone.
According to Shang Bu Huan's impostor, he was never given a name or identity of his own after the Xuan Gui Zong took him in when he was a baby. This may be true of all nameless Onyx Demon members who work under Mie Tian Hai. It might be possible that Can Xiong, Lie Mei, and Diao Ming were never given names until Mie Tian Hai gave them proper names after they fully mastered most of his arts.
The reason Xing Hai and Seven Blasephemous Deaths don't tell Lou Zhen Jie their real plan for traveling to the past to receive the Seven Blasephemous Deaths' original body and resurrect her is that if they did so, he would either refuse to go along with and flee with Seven Blasephemous Deaths or plan to destroy it, since she wouldn't be able to return to her real body again since Lou Zhen Jie prefers her sword form over her true appearance.
Why is Huo Shi Ming Huang not concerned about Zhao Jun Lin's impending resurrection? Because as the Emperor of Xi-You, he's already doing what she wanted their royal family to do in the first place and thus has nothing to personally fear from her. If anything, she might be a willing ally at that point.
Lin Xue Ya's agenda to steal the Tian Xing Jian for his own gain is very unsettling when it's shown that he was able to convince two of his enemies, Xing Hai (by telling her that Mie Tian Hai could kill someone like her) and Sha Wu Sheng (by telling him that he can have his head afterwards), to join his team. He had intentions to kill Xing Hai after using her for a trial and he would easily be able to kill Sha Wu Sheng with a powerful weapon. Somewhat averted that Xing Hai ended up being Evil All Along, probably more evil than Mie Tian Hai himself.
It makes sense that Azibělpher shows Lang Wu Yao a glimpse of the future to let him know that if he chooses to change the past by saving Mu Tian Ming's life, it will make Shang Bu Huan lose his reason for leaving Xi-You and will result in the demon god Yao Tu Li destroying the world because there will be no one to re-seal the demon god again. Lang Wu Yao's actions will change a major course of the timeline.
One of the major changes from Shang Bu Huan not being around is Dan Fei's death at the hands of Xuan Gui Zong's minions, since Shang Bu Huan was the one who saved her life. Plus, it will mean she will be the last Hu Yin Shi to die out and join her brother in the afterlife, and she will never meet her future husband to a start a family with.
The reason Zhou Xun Yin decides to spare his son, Lang Wu Yao, after giving birth to him is because she has no idea what he looks like after she loses her eyes to her former lover, who is a demon. It is possible she thinks her son looks like her instead of his father. If Azibělpher hadn't destroyed Zhou Xun Yin's eyes, she would have either abandoned him in an isolated place and left him to die or killed him instantly for looking like her ex-lover.
