Note 1: This is NOT a list of character skills, just a list of xianxia terms in Grandmaster of Demonic Cultivation (GDC) aka Mo Dao Zu Shi (MDZS) that are likely to come up in tags, so I might as well give a brief explanation of them.
Note 2: This is by no means a full list of what goes on in canon, just a primer I slapped together from reading the GDC book-- the novels published by Seven Seas have glossaries at the back-- and other xianxia novels and comics, and a bit of extra research to fill in some gaps. There are people who have done even deeper dives into the genre, like whoever runs the Immortal Mountain site. If I made a mistake somewhere or the official translations contradict anything I've already written, I'll make the necessary edits.
Note 3: I'm a Southeast Asian of Chinese descent living in a Southeast Asian country with close historical and cultural ties to China. Some of the Chinese culture prevalent in this region has changed over time and distance, but the roots are still the same, so I try to write what knowledge I do have in ways I understand them to make them more accessible.
The traditional type of qi that GDC cultivators use, which uses just the qi they have accumulated in their bodies. The primary way for cultivators to accumulate spiritual qi is to absorb it from their surroundings through meditation, because spiritual qi is an energy that flows through all living things, even in the atmosphere, it might as well be the default state of qi. Other xianxia works also introduce herbal medicine created from magical fauna and flora using alchemy that do the same job, but said medicine doesn't seem to exist in GDC. Or maybe it does, and no one wants to admit to using performance-enhancing drugs.
This method of cultivation is considered the orthodox way, and their culture tends to consider cultivation using other sorts of qi as unacceptable or taboo (usually for good reason).
"Orthodox" doesn't always mean good, and "unorthodox" doesn't always mean evil, though. "Orthodox" simply means that the practice is more socially accepted, sometimes with a long history of being associated with good, righteous people. Unorthodox practices allow cultivators to gain unique powers very quickly, but they're always risking themselves or bringing harm to others hence the bad but justified reputation, while orthodox practices take a long time to show results, but are safer. Of course, this means that orthodox cultivators don't look kindly on unorthodox cultivators, and fighting one to bring them to justice is considered acceptable by GDC's cultivators.
spiritual energy
This method of cultivation is considered the orthodox way, and their culture tends to consider cultivation using other sorts of qi as unacceptable or taboo (usually for good reason).
"Orthodox" doesn't always mean good, and "unorthodox" doesn't always mean evil, though. "Orthodox" simply means that the practice is more socially accepted, sometimes with a long history of being associated with good, righteous people. Unorthodox practices allow cultivators to gain unique powers very quickly, but they're always risking themselves or bringing harm to others hence the bad but justified reputation, while orthodox practices take a long time to show results, but are safer. Of course, this means that orthodox cultivators don't look kindly on unorthodox cultivators, and fighting one to bring them to justice is considered acceptable by GDC's cultivators.