Since we have no casting to fawn over, I'll put together my own fictional cast for the characters. Of course my taste is limited mostly to Chinese actors since I watch more Chinese dramas, so no doubt the movie cast would be completely different from mines when it comes out. If you have your own ideas about who should play who, feel free to write them out in the comments, I'd like to see too!
I know he's a singer and an idol actor and usually does modern dramas, but his look seems to fit Su Mo enough. Su Mo is the Hai Huang (Sea King), as jiao-ren are described as having beauty that surpasses all other races and the king of jiao-ren naturally, he's even more striking so I don't think anybody can really fit the bill. I imaging Su Mo to have single eyelid though, since that seems more 'elegant' and his sharp and slightly feminine looks is pretty suitable too since jiao-ren are known to not have gender until they fall in love and then either become male or female, so Su Mo, even though he is male he has to have a slightly feminine touch to his handsomeness I think. Plus this guy looks kind of like Lee Junki. Not sure if Chen Xiang can pull off blue hair though! Su Mo is also a bit of an anti-hero. He's a puppeteer and carries around a creepy doll replica of himself which he claims is his twin little brother Ah-Nuo, but it is actually his Mirror. He practices a shady magic originating in the Central Plains called Li, which to the next degree becomes Jing (Mirror), resulting in his psyche being split in half. He forces his 'evil' half into the doll and controls it with strings but it frequently gets out of hand. Li has allowed him to become very powerful in a short amount of time. This turns Su Mo into an even more complex person on top of his already complex identity and persona. Su Mo is a very thrilling character to read and he's very unpredictable, but one thing is sure: he has one responsibility that he holds above everything else in his world, which is to free the jiao-ren in Yun Huang from enslavement and bring them back to the Jade Sea. Su Mo is like the Moses of Yun Huang haha, leading his people out of slavery and back to their home in the Jade Sea. I can imagine Su Mo as someone who lets out a condescending smirk from time to time and other times, his eyebrows are locked tightly together enduring who-knows-what's-going-on-inside-his-hea
Bai Ying is a ghost, literally. She's the designated wife of the crown prince Zhen Lan, but she threw herself off the White Tower after acknowledging her romance with a jiao-ren slave, but was saved by the three goddesses of Yun Huang and later died a hero, sacrificing herself to open the entrance into the Colorless City so that the Kong Sang people could escape from the invading Bing Yi. Bai Ying is the reincarnation of the legendary Queen Bai Wei of Meng Hua Dynasty thousands of years ago, but she doesn't have the wisdom nor bravery of Queen Bai Wei. Instead, she is soft-hearted and kind to a fault, almost weak in the eyes of some. The Kong Sang people love her despite her supposed taboo rumors with Su Mo, which are actually true. She is like the Princess Diana of the Kong Sang people. Lui Shi Shi has a very soft and gentle aura, which I think is perfect for Bai Ying. The face playing her has to be a face that can never play a scheming, corruptable character, a 'Guanyin'-like face. Lastly, Bai Ying has white hair because she is a ghost. She is also a Sword Saint and continues to hold her sword, defending the weak even in her ghost state. Her unresolved desires from before she died were so strong that it kept her soul from dispersing, turning her into a being called a yin-ling. At night, she can solidify her soul into a physical state, but in daylight she has no power and the sun can destroy her. Her relationship with Zhen Lan and Su Mo are very ambiguous because she is already dead. It's already too late for love, but she still cares deeply for them. Her only purpose of existence is to complete the promises she made to the Kong Sang people, defeat the Bing Yi so that the Kong Sang survivors could come out of the Colorless City and return to Yun Huang. Once her desires are fulfilled, her soul will disperse.
Zhen Lan is the last Crown Prince of the Meng Hua Dynasty before it fell into corruption and got overthrown by the Bing Yi. During the hundred years of Cang Liu Dynasty ruled by the Bing Yi people, Zhen Lan had been cut into pieces and sealed off in ice on the mountains at the edges of the four corners of Yun Huang to ensure that the Kong Sang people could never return to power. Due to the power of king's blood in his veins and the Huang Tian ring on his finger, he cannot be killed so he had to endure this humilliation. Even in his last moments before he was cut to pieces, he did not forget to encourage the Kong Sang people to wait for his return and plant seeds of hope inside their hearts and give them a reason to wait, to imagine a day when the Kong Sang people would take back Yun Huang from the hands of the Bing Yi. Zhen Lan is someone who is extremely strong, optimistic and wise. I love Su Mo and Bai Ying, but honestly my favorite character in the series is Zhen Lan. After watching Shawn Dou in Princess Agents, I thought he is the perfect face for Zhen Lan. Behind his bright smile and lighthearted demeanor, there is a lot of pain and helplessness, but also deep love for his people and a very big and noble heart that can hold all of Yun Huang inside. Although I haven't read to the end of Jing Yet, but from mentioning of him in the Feather series, Zhen Lan supposedly lost both Bai Ying and Su Mo, both people that fought for Yun Huang with him and became very close friends with. All he was left with was a noble name on the pages of Yun Huang's history. He never married and spent the rest of his life alone on the White Tower. His life was a brilliant legacy but he was actually just a very simple and unfortunate guy. In the end, he gained Yun Huang but lost everything that ever mattered to him.
Na Sheng is the first character that the reader encounters, she is also the eye from which we see Yun Huang, as an outsider. She is a Miao girl from the Central Plains and travels with a band of refugees, crossing the penninsula and the Mushitage Mountains into Yun Huang, searching for a better life. Travelling with her is Mu Rong Xiu and Su Mo, both strangers which she will grow close to as she enters Yun Huang and history unfolds itself. I think Na Sheng is very relatable. She's simple, has simple desires, romantic, brave, and comes off kind of stupid sometimes. She doesn't have any baggages so unlike the other major characters, she is a free soul, but that changes when she meets Zhen Lan and her life gets flipped upside down when the Huang Tian ring chooses her as its bearer. She reminds me of Demigods Semidevils Duan Yu, who learns a powerful skill but sometimes it works and sometimes it doesn't. It's frustrating in a funny way. Na Sheng is a very sweet girl and I think Mao Xiao Tong's face is perfect for her. I first noticed Mao Xiao Tong in Love O2O, and her chirpy, cute portrayal of Wei Wei's friend immediately came to my mind for Na Sheng.
Mu Rong Xiu is a half blood child, his mother is a jiao-ren and his father is a rich merchant from the Central Plains. He is a young but resourceful guy, calculating too. His good genes earns him the attention of Na Sheng at first, but his indecisive and careful personality makes her loose her interest quickly. Mu Rong Xiu is a good guy at heart, is brave when it comes to making life and history-changing decisions and is very smart. I haven't finished reading the Mirror series yet so most of what I know about this guy is from the first two books of Mirror and his family's legacy that was passed down through history inside the Feather series. As a half-merman, his willingness of allying with the Kong Sang people was seen as a betrayal to the jiao-ren race, but it was also his participation in the overthrowing of the Bing Yi that solidified his family name in Yun Huang for 900 years to come. Mu Rong Xiu is a smart guy, his outer appearance should be smooth and friendly, gentlemanly and with good manners. I've always gotten this kind of impression from Ma Tian Yu's previous roles, although some of them were more love-sick and on the young and gullible side, but that's probably because of the roles he's usually casted in. Mu Rong Xiu seems kind of gullible at first glance too, so actually this is perfect.
Yun Huan is a Bing Yi, meaning he has blond hair and blue eyes! Since my fictional cast is all chinese people, I'll just go with a chinese face for him too. Yun Huan is Po Jun, the legendary "God of War" figure of the Bing Yi. He's a very sad and tormented guy so it's ok that Chris looks a little emo. Chris also looks great in blond hair too, so that's a good thing. He's also got that stubborn and kind of arrogant look (I swear I'm not a hater) that Yun Huan would probably have. Yun Huan is another very strong character but he's kind of twisted and his bottom line in terms of ethics is pretty low. He gets used by his people, lacks freedom and happiness given his dire circumstances, but inside he is a desperate little boy that is holding dearly onto his last matchstick. He has a romance with his shifu, kind of like Yang Guo and Xiao Long Nv inside Condor Heroes, but much much sadder. Out of all of Yun Huang's characters, I think the author was the most cruel to this character, but he is a toughie that endures 900 years of the author's torture haha. The author finally relinquishes her torment of him inside of the Feather series and finally gives him his happy ending. Such a sad, sad character. Chris is perfect, appearance-wise.
Mu Yuan is another legendary figure that is passed down in history. She is one of the Sword Saints, but although there have been many generations of Sword Saints, she is the only one who went down in history with honor rivaling that of Su Mo and Zhen Lan, both kings. Mu Yuan's identity is actually very complicated and when she dies, things get even more complicated! But that's for another book series (Feather). Mu Yuan is described as always wearing white, pale, sickly (she was severely injured), sits in a wheelchair. Her temperament is rather mellow and she lives in a tomb, sealing herself away from the conflicts of the world. Sadly, fate still finds a way to entangle her and she can't help but get caught in it, causing her to pull out her sword again. Mu Yuan is kind and merciful, although she is a Kong Sang, in her eyes there is no difference between Kong Sang people, Bing Yi, or jiao-ren. To her, all life is equal and she will protect anyone when she sees injustice. Liu Tao is the perfect face for Mu Yuan I think, because she has this cultured, mature aura about her. I love watching her dramas and although she does play fiestier characters sometimes, I think she has the clean and quiet feel that Mu Yuan has.
Xi Jing is not that young in age, I think he is in his mid to late 30s, I don't really remember. Xi Jing is Bai Ying's shixiong, her only shixiong in fact, because the Sword Saints only have two disciples per generation and they have prominent status within the Kong Sang people, seen as the sword-weilding protectors of the people. Xi Jing later became a general of Zhen Lan, helping him to take back the throne from the Bing Yi. Xi Jing is a heroic character and he is a bit of a drunkard in the beginning, but throughout the story he also gives a lot of comic relief for this otherwise heavy story. When he is fighting or when he is doing important things though, he is no- nonsense! Feng Shao Feng is a bit older than my other castings, but he is still fresh enough to take on a semi comic character I think. I like his versatility and he works for joker Xi Jing as well as serious Xi Jing.
I haven't seen much of Xiao yet, but I know she is fiercely loyal to Yun Huan even though she is just a slave. She is a jiao-ren, but instead of aligning herself to her kin, she chose to stay by her owner's side and continues to follow him until her death. She has the signature blue hair and blue eyes and beautiful features of her race, but she is also described as being gentle, obedient and stubborn. Janine has the stubborn but soft look that Xiao has to have. She is also another sad character that doesn't regret her decisions but suffers through them still. Xiao is also an older sister, so she has to look a little mature too, but not necessarily in age. Xiao and Ting, her younger sister, were separated when young and died in a crossfire between the jiao-ren forces and Bing Yi forces of which Xiao and Yun Huan took part in. Xi Jing was Ting's owner who she is very lucky to have because he treats her like a friend and younger sister, although there is supposed to be a hint that Ting is in love with Xi Jing, but she did not live long enough to see it bloom into anything. Xi Jing taught Ting some of his sword skills even though he did not officially take her as a disciple, but if he had not kept from teaching her the last and most powerful of the Sword Saint's skills, she might have survived. Xi Jing blames himself for her death even though it was Yun Huan and Xiao that killed her. Even if she did survive though, Ting's love for Xi Jing would not have been accepted by both the Kong Sang people and those of her own race because the pact between Kong Sang and the Jade Sea had yet to happen and the two races were still at odds, thus taboo and frowned upon. Ting misses her sister dearly and has been looking for her since they separated. She knows Xiao had been bought by the Bing Yi and is probably being used as a puppet pilot in one of their Fengxuns, large and powerful flying war machines. What she doesn't know is that her sister had never been turned into a puppet and had chosen to betray her own people. Tang Yi Xin has a very youthful and little-sisterly vibe from her previous roles, which I mostly got from Noble Aspirations actually. I've only seen her in a handful of dramas, but she seems to fit Ting's description. While Xiao is mostly quiet and rather collected, Ting is a hopeful and happy girl despite her slave status. Both sisters have blue hair and blue eyes though, so maybe it'll just be nice to imagine and might not look so great in reality haha. Blue hair really is rather hard to pull off!
These three characters are kind of special. First of all, Bai Wei is supposed to share exactly the same appearance as Bai Ying, so her face will be Lui Shi Shi's too. Lang Gan never actually shows up in the story since he's a historical figure, abeit a very important one! Zhi Zhe is always under a hood so his appearance isn't important haha. I'm not going to give away his identity here too, so we'll just skip his casting.