Info;

SYNOPSIS
A man from a fictional period in ancient China. Wei Wuxian comes from a wuxia story, a low fantasy-esque genre of Chinese literature where humans practice some kind of magic through the harnessing of qi/energy from the environment and the practitioners' own bodies. Practitioners aka cultivators form sects and hold high social status. However, Wei Wuxian is a disgraced cultivator who doesn't follow conventions, prefers acting like a commoner than gentry, and his practices of controlling ghosts and corpses are condemned as "evil". His unstable mental and emotional state due to his practices don't help these allegations.
At his core, he often says or does stuff for the shock factor or attention, or just to amuse himself-- while he does genuinely like to mess around, he will back down if told to do so (eventually)... unless it's from someone he's pegged as an asshole. Then he just annoys them even more. He's also prone to Inventor Brain, where he finds something interesting to work on and tends to forget everything else, like bodily needs and personal safety. Despite being called evil, Wei Wuxian has a moral code that he never deviates from, and is more concerned about helping people than taking care of himself to the point of being self-sacrificing.
BASICS
Canon: Grandmaster of Demonic Cultivation aka Mo Dao Zu Shi (Chinese BL wuxia novel)
Canon Point: During his Yiling Patriarch era, which spans his early 20's.
Name: Wei Wuxian (Eastern format, last name first), birth name Wei Ying
Aliases/titles: The Yiling Patriarch
Age: 22-23
Gender: Cismale (he/him), but sometimes jokes about being a wife and a mom
Species/race: Plain ol' human.
FIRST IMPRESSIONS
Fashion: Wears the costumes you typically see in Chinese historical-based media-- the kind that look like ancient Chinese outfits, but take a lot of artistic liberties for aesthetics rather than historical accuracy. Wei Wuxian prefers to wear black and red robes, and sometimes he'll wear other colors, but they tend to be neutrals like grey and occasionally white.
Spiritual/magical/aura: He's full of negative, yin-aligned qi (that can make him aggressive and nasty), but said qi doesn't follow the typical pathways that qi takes in someone's body.
Height: 186cm (6'1.22")
Build: Long limbs, has a body for running and swimming. Also apparently he has really nice legs, a trim waist, and a big butt. No, really, the author describes his lower half in detail twice in the same chapter (Incense Burner part 2).
Hair: Black, long, and wild, with a slight curl at the ends. He always uses a red ribbon as a hair tie.
Eyes: Brown or grey depending on the artist/adaptation-- the novel never says what color they are, hence this divergence in his interpretations. I also like to take from the 2D adaptations and say that his eyes glow red when he's using his ~forbidden powers~ aka demonic cultivation. Let me have this, just for the cool factor.
Voice: He has so many actors, depending on the medium, language, and age. His performers in the main mediums are Zhang Jie (donghua), Xiao Zhan (live action), and Lu Zhixing (audio drama). A note: His voice in the live action is dubbed over by Lu Zhixing because of Chinese drama conventions, but I like some of the gestures and body language Xiao Zhan puts into his performance.
Language: Speaks Mandarin. Southwestern Mandarin? Or whatever the main dialect(s) in Hubei was (were?) thousands of years ago.
Scent: Not pleasant, primarily blood, soil, ink, and dead bodies. Not for a lack of trying, but at his canon point, Wei Wuxian lives in a cave and is deep into his demonic cultivation, which is basically necromancy.
Hand dominance: Right-handed
Literacy: Can read and write. However, it's often stated by other characters that his calligraphy is awful.
Triggers: Dogs-- show him a dog, and he will drop everything to run away. On the other hand, threatening or harming the people he cares for may prompt a violent reaction or a nervous breakdown. Or both at the same time.
Other: Has a burn scar in the shape of a stylized sun just over his heart.

abilities
demonic cultivation
This sort of practice makes use of the qi or energy called resentment that is typically generated by negative feelings-- and the dead can have a lot of negative feelings. With this qi, Wei Wuxian is quite attuned to the spirits of dead humans and can speak with them directly, give them orders and have them fulfilled to some degree of success, dive into their memories, temporarily bind spirits to human-shaped items, puppeteer corpses, and reanimate more when needed. (A lot of people call it necromancy, and I don't disagree.)
The main drawback of this cultivation is that resentment affects the practitioner's mental and emotional state, and prolonged use can actually kill them. This is made more dangerous when there's a low barrier for entry-- practicioners don't need to have a golden core or an internal repository for spiritual qi, which takes regular cultivators years of hard work and training in order to develop and master. Plus, the older someone is when they start, the more difficult it is to form a golden core, adding an additional layer of difficulty to working with spiritual qi.
However! The proper name of this form of cultivation is the Ghost Path or gui dao, solely because of where the resentment comes from-- ghosts and demons are entirely different beings in the context of canon, the former being formed from dead humans and the latter being formed from living humans, and Wei Wuxian never takes the qi of the living, so he's not really a demonic cultivator. This misnomer gets more awkward when actual demonic cultivators start coming out of the woodwork, especially since they're his fans and copycats, and he gets lumped in with them all the time.
talismans & arrays
Wei Wuxian is a master of both, able to write talismans quickly, repair and activate arrays on the fly, modify the diagrams on existing pieces, make talismans and arrays work together, and even create his own. He's not able to create new ones under duress, but give him time and a lot of extra materials (and some space, because explosions are going to happen), and he'll come up with something revolutionary. In fact, a lot of his ideas and creations end up being used by other cultivators because they're too useful to ignore, like the talisman that lures resentful creatures, and the compass that points towards resentful qi.
chenqing
Musical cultivation is all over the story and its various adaptations but not really explained in-depth (unless I missed something). Wei Wuxian isn't even an expert in it, nor did he formally study it, so he's not on-par with the in-universe experts. The best I can do is say that he plays notes and pushes qi with intent into them, and that's how he controls corpses and puppets.