- Name: Procyon
- Faction: Cybran Nation
- Description: Former Cybran Homeworld
- Terrain: Red Wasteland
Once a rough, but livable world, Procyon is now little more than a grim reminder of the costs associated with the birth of the Cybran Nation.
Dr. Gustaf Brackman, literal and figurative father of the Symbionts, established an all-Symbiont colony on Procyon. Mistrustful of the old Earth Empire, but still a loyal scientist, Brackman established the colony in 2650 and applied for independence in 2663. The Empire responded with force and occupied Procyon. Continuing difficulties between the two sides escalated and soon the Symbionts were fighting a guerrilla war against the occupying Imperial troops. The Earth Empire activated the loyalty programming installed in all Symbionts to keep the rebellion from spreading, but Brackman had already disabled the programming in his followers.
The Imperial Commander, tired of the constant guerrilla attacks, simply began methodically scorching the planet with strategic weapons. Brackman and his followers were forced to flee; Procyon was reduced to nothing more than a desolate wasteland and it was later abandoned by the Earth Empire.
There are rumors that the Cybran Nation have begun to recolonize Procyon, but those rumors cannot be substantiated. What was confirmed that during the Cybran and Aeon campaigns Procyon once held QAI's Mainframe during the events of Supreme Commander 1. After a brief, yet massive battle on the planet's surface, QAI decided to move its Mainframe to Pearl II so it could not risk being compromised.
The end of the Infinite War was the start of Forged Alliance. It seems that the UEF were the real winners of the original campaign, since there was no galactic peace as the end of the Aeon campaign suggested, and the Cybrans were still hopelessly outgunned. In the Forged Alliance campaign, Procyon and Seraphim II are not mentioned, so it seems that they were destroyed as the UEF campaign claimed at the end. However, this theory cannot be proven as there is a short time between the end of Supreme Commander and the start of Forged Alliance. In that time the Quantum network might have been repaired by the factions after the Cybrans destroyed it. Also there might have been a ceasefire after the Princess' message, just no actual alliance. Procyon is probably not mentioned in Forged Alliance because it was no longer a suitable location for a colony, as the UEF have undoubtedly done with planets no longer of use to them.
The fate of Proycon is unknown.