What is the main conflict in Lord of Light by Roger Zelazny?

"Lord of Light" is a science fiction novel that takes place on a planet that has been inhabited by people from Earth for many generations. The first settlers of the planet have developed technology that allows them to magnify their mental powers and transfer souls into new bodies. They have used this technology to create a mythology based on the Hindu religion, positioning themselves as gods with unique powers and keeping the majority of the inhabitants of the planet in a state of technological ignorance. The gods live in a domed city called Heaven and are led by the gods Brahma, Vishnu, and Shiva.