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.