The magic system (術式 jutsushiki, lit. "arts expression/style") refers to the methodology of a practitioner's abilities and Devices. Two main systems are recognized in the series: the Midchilda system, and the Belka system. The Belkan system is further subdivided into Ancient Belka and Modern Belka, with the latter being an emulation of the Ancient Belkan one by using the modern Midchildan one as basis. Practitioners of Midchilda and Belka systems can be told apart by the form of their respective magic circles.