Chi, also known as Qi, (PROSE: Opioid Painkiller of the People [+]Loading...["Opioid Painkiller of the People (short story)"]) was energy linked into every cell of all human beings, but witchbloods had more of this energy than most. (PROSE: Warring States) Compassion needed this energy in order to survive, which led to her manipulation of Cousin Octavia and Liu Hui Ying in an attempt to continuously drain their chi and then subsequently to the creation of the City of the Saved. (PROSE: Warring States, Of the City of the Saved...)
In addition, chi had other properties, such as with proper training anyone could infuse their strikes to add significant force, or how lines of chi flowing throughout the land can disrupt Faction modes of transportation. (PROSE: Warring States)