In the Witcher universe Chaos (also known as the Force, Power, or primordial Chaos), is the power which is harnessed and used by mages. Sources are innately sensitive to this magical force but are usually unable to master it and many go mad. The Force is said to have become much more prominent in the world after the Conjunction of the Spheres.
Places where Chaos is strongest and most accessible are known as intersections. Strangely, cats are sensitive to these places. Dragons are as well, but as they are considered magical beasts, this seems less strange.
Notes
- According to Mousesack, a virgin can't use the Force, which is how he suspected Pavetta was pregnant.[1]