Virochana like his father was a great devotee of Lord Vishnu, was a virtuous ruler and didn't oppose the devas, at least knowingly. Virochana on Shukracharya's advice decided to make penance to the sun god, Surya. But the day on which he had decided to go to the mountains for his penance happened to be the day his son was born, after he had seen his son, he went to the mountains for the penance. After about 10 years Surya was pleased with the penance and gave him a crown which would protect him as long as he wore it. Upon returning home he learnt that his son Mahabali had grown old enough to start the learning phase of his life or Brahmacharya and that was the day on which he would leave to begin his brahmacharya. As Virochan was a devotee of Vishnu he ordered that all the temples that belonged to the devatas inside his kingdom be turned into temples of lord Vishnu and that yagnas be performed only to Lord Vishnu. This caused the devas to starve as the offerings that were given to them in yagnas were their food. Thus Indra made a plan to kill Virochan, he had to use trickery because Virochana had protection of his magic crown. So, on the day Mahabali's Brahmacharya completed, Virochana and Devamba wanted to bring him back home themselves and as this was a personal cause, so instead of using a royal carriage, they used a simple chariot which Virochana himself drove. When they were crossing a particularly dry piece of land, Surya increased his brightness, so they started to get extremely thirsty with no source of water in view. Suddenly a hut came into view. Virochana stopped the chariot in front of the hut. Inside the hut were 2 sages, who were actually Indra and Varuna disguised. Virochana asked them for some water and the sages told him and Devamba to rest for a while inside the hut while they fetch some water from a well behind the hut. Inside the hut Virochana and Devamba waited and eventually fell unconscious from the thirst. Indra removed the crown from Virochana's head and threw it into the well, then Virochana regained consciousness and upon seeing Indra attacking him drew out his own sword. Varuna on seeing that Indra can't defeat Virochana alone joined in the fight. Finally both of them were able to kill Virochana and as Indra knew that Shukracharya had the Sanjeevni Mantra which can revive the dead and also knowing it will work only if the body existed, he set Virochana's corpse on fire. Devamba died of grief. This incident is what caused Mahabali to oppose the devas since his father had seen him only twice, when he was born and when he was leaving for brahmacharya and also because his father didn’t receive proper funeral rights.
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