Asurayuddha or Asuravijaya is a type of unrighteous war
mentioned in Kautilya’s Arthashastra. In this type of war, the conqueror
conquers like demons. They seize land, money, and women and make people slaves.
It is called Asura yuddha because it is believed that demons practiced such
means of warfare.
All heinous, illegal and forbidden methods of warfare are
used for obtaining victory in this type of war. There is no direct or straight fight
in Asuravijaya.
Secrecy, guile, charm spells and cheating are widely used to
attain victory.
Wars according Hindu scriptures like the epics, Puranas and Shastras are broadly classified into - dharma yuddha and Adharma yuddha or kuta yuddha; righteous and unrighteous war. Kautilya in his Arthashastra further classifies the adharma war into two as lobhavijaya and asuravijaya. Asuravijaya or asurayudha is one in which the conqueror conquers like a demon seizing the land, money, sons and wives of the defeated king, whereas lobhavijaya, the war is waged only out of greed to obtain land, money or both.
Asura yuddha is so called because the asuras were experts in such means of warfare as accounted in the Vedas. Asurayuddha is most heinous of all kinds of wars involving illegal and forbidden methods for obtaining victory. It does not involve direct or straight fight at all. In asura yuddha, secrecy, guile, charm spells and all unfair means are employed to win. It was also termed as mantra yuddha. Sukraniti also recognizes this.
Kautilya advises an inferior powers to keep away from such demonic conquerors by offering them land and wealth. Such kinds of war were rarely resorted to in cultured civilizations as it was ruthless and characteristic of primitive tribes where codes of chivalry were not defined. But it does not mean that this war was unknown to cultured civilization for they were taught all kinds of warfare for the purpose of defense as last resort.