Mahabharata
While the marriage of Iravan's parents is mentioned in the first book of the Mahabharata, Adi Parva (the Book of Beginnings), both the birth and death of Iravan are mentioned later, in the sixth book, Bhisma Parva (the Book of Bhisma). In this sixth book of the epic, Arjuna, the third Pandava brother, is exiled from Indraprastha (the capital city of the Pandava kingdom) to go on a one-year pilgrimage as a penance for violating the terms of his marriage to Draupadi, the Pandava brothers' common wife. Arjuna reaches the north-east region of present-day India and falls in love with Ulupi, a widowed Naga princess. The two get married and have a son named Iravan; later, Arjuna proceeds with his pilgrimage, leaving Iravan and Ulupi behind in Nagaloka, the abode of the Nagas. Iravan is described as being born parakshetre, literally "in a region belonging to another person", interpreted by Hiltebeitel as "upon the wife of another". Iravan grew up in Nagaloka, protected by his mother, but was rejected by his maternal uncle because of the latter's hatred of Arjuna. After reaching maturity, Iravan, hoping to be reunited with his father, departs for Indraloka, the abode of the god Indra, who is also Arjuna's father. Upon meeting his adult son, Arjuna requests his assistance in the Kurukshetra War.
Thus Iravan finally reaches the battlefield of Kurukshetra to assist his father and Pandavas against their cousins and opponents, the Kauravas. On the first day of war, Iravan fights a duel with Srutayush, a Ksatriya king who had been a daitya (demon) called Krodhavasa in a prior incarnation. Srutayush is later killed by Arjuna. On the seventh day of war, Iravan also defeats Vinda and Anuvinda, the princes of Avanti, who are later killed by Arjuna.
On the eighth day of the war, Iravan combats the princes of Gandhara, sons of king Suvala, and the younger brothers of Shakuni, the treacherous maternal uncle of the Kauravas. The brothers Gaya, Gavaksha, Vrishava, Charmavat, Arjava, and Suka attack Iravan, supported by the whole Kaurava army, but Iravan's army of Nagas slays all but one of their opponents. Iravan, the "chastiser of foes"—versed in maya (illusion)—slays five of the Gandhara princes in a sword fight; Vrishava alone escapes death.
Agitated by this reversal, the eldest Kaurava, Duryodhana, orders the rakshasa (giant) Alamvusha (or Alambusha), son of Rishyasringa, to kill Iravan. This time Alambusha, as well as Iravan, uses illusion in combat. Alambusha attacks Iravan with a bow, but Iravan counters, breaking Alambusha's bow and slicing the giant into several pieces. Alambusha's body, however, reconstitutes itself. Then Iravan assumes the form of the serpent Shesha (Ananta), and his serpent army surrounds him to protect him. Alambusha counters this by assuming the form of Garuda (the eagle-man), the eternal foe of the serpents, and devours the serpent army. Ultimately, Alambusha kills Iravan by cutting off his head, though Iravan is later avenged when Ghatotkacha, his cousin, finally kills Alambusha.
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