His company was contracted to terraform Ceres Alpha. He refused to stop the process even when remains of a prior civilisation on the planet were discovered. He saw the psychic children being born on Ceres Alpha as a threat to the project and wanted them dead.
When Domecq started dissecting one of the children to learn more about them, the others lashed out and killed Domecq. They also turned a mind probe Tyran was using back on himself. Forced to face all the terrible things he had done to achieve his position, he died from shock. (PROSE: Dark Progeny)