Omnus’ tale is a depressing one. Eons ago, the planet was inhabited by multifarious forms of life. The major sentient race of the planet eventually developed technology so far that they let their machines control every aspect of their lives. The machines were then given the minds of the inhabitants of the planet, and then, all life on Omnus was also eventually transferred to machines. There were originally two factions of machines on Omnus, the Gathorans and the Defilers, but the latter, who lacked a moral code, unlike the former, forced the Gathorans out.
Omnus was destroyed when Dark Madder took the Engine of Creation from it after using the planet’s vast computing Core to find out how to change the Engine to one of Destruction. Prior to its destruction, however, it had become a place devoid of non-machine life and atmosphere. Everything on the planet was artificial and its biosphere was used as raw material and fuel for the machines of the planet.
This planet was also notable because it was the source of many new technologies, e.g., tractor beams, cloaking, etc.