Parallel universe (Code Silver)
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The Cybermen of the Cyber-Mainframe originated from a parallel universe which was speculated by Kate Stewart to be neither N-Space nor "Pete's World".
By the time Hive Section 49 attempted to commence the dimension seeding of N-Space, the Cybermen of the Cyber-Mainframe had conquered 48% of this universe. The Cyber-Controller who led this invasion attempt analysed that all available data within the Cyber-Mainframe indicated that the Cybermen would take full control of this universe within 7849 years, using this to reaffirm its belief that "Cyber-forces [were] unstoppable". (AUDIO: Code Silver)
