Chi and its use can be considered a form of magic, although a more accurate description would be a source of energy located deep within a mortal's being. With intense concentration and training, mortals may tap into this energy, leading to increased strength, speed, and sharpened senses. All mortals have chi, although the vast majority of mortals never truly access it.
With the death of Patron, chi became weakened and those with a mastery of it became increasingly rare. However, the efforts of Nyubar have helped rekindle and reinforce chi within mortals. Still, the years when Patron walked the earth had the most chi users, and in those days Yinshung were not as uncommon of a sight.