Barong is a character in the mythology of Bali. He is the king of the spirits, leader of the hosts of good, and enemy of Rangda in the mythological traditions of Bali. Banas Pati Rajah is the fourth "brother" or spirit child that accompanies a child throughout life. Banas Pati Rajah is the spirit which animates Barong. A protector spirit, he is often represented by a lion, and traditional performances of his struggles against Rangda are popular parts of Balinese culture. The Barong is often portraited with two monkeys.

The Barong is the magical protector of Balinese villages. As "lord of the forest" with fantastic fanged mask and long mane, he is the opponent of Rangda the witch, who rules over the spirits of darkness, in the never ending fight between good and evil. During the Galungan Kuningan festivals, the Barong (there are many types, including barong ket, barong macan, and barong bangkal) wanders from door to door (nglawang) cleansing the territory of evil influences.Barong and Kris dance like the kecak dance the Barong and Kris dance is a battle between good and evil spirit. Barong can take various forms but in this dance he takes the form of the dance Barong Keket, the most holy of the Barongs. The Barong Keket is a strange creature, half shaggy dog, half lion and is played by two men in much the same way as a circus clown-horse. His opponent is the witch Rangda.

The fight between Barong and Rangda is also the topic of traditional narratives, usually performed in the temple of the dead. The most famous is the story of Calonarang, a widow from Jirah who is furious because she cannot find a suitable husband for her daughter Ratna Manggali. All the eligible young men are scared of her black magic, so she gets revenge by wreaking havoc over the kingdom of Daha. The king, Erlangga, tries to punish her, but all his attempts fail. She kills all the soldiers he sends to destroy her. Then Rangda decides to destroy Daha. She summons all her disciples and in the still of night they go to the Setra Gendrainayu cemetery, to present offerings of dead flesh to Durga, the goddess of death. Durga agrees to the destruction, although she warns the witch not to enter the city of Daha. But the witch does not heed Durga's advice and the kingdom is soon hit by grubug (a plague) and the villages quickly become cemeteries, people dying even before they can bury their dead. Corpses are scattered everywhere and the stench is unbearable.The only person who can defeat the witch is Mpu Bharadah. At the king's request, Bharadah sends his disciple Bahula to steal Calonarang's magic weapon.

Bahula pretends to ask for Ratna Manggali's hand in marriage, and while the witch is away, Bahula steals the magic weapon with the help of Ratna Manggali. Then he gives the stolen weapon to his teacher Bharadah. The weapon turns out to be a manuscript containing the key to ultimate release (moksa) which has been used upside-down by Calonarang. Bharadah goes to Daha to challenge the witch. With the help of the Barong, she is defeated. Before being killed, she asks to be released from her curse and purified.