According to one account, Earth's twin planet Mondas, on which the Mondasian Cybermen originated, (TV: The Tenth Planet [+]Loading...["The Tenth Planet (TV story)"]) existed in "an alternate universe". (GAME: Worlds Apart [+]Loading...["Worlds Apart (video game)"]) This stood in contrast to various accounts agreeing that the genesis of the Cybermen and destruction of Mondas were events within the timeline of the Doctor's universe. (AUDIO: Origins of the Cybermen [+]Loading...["Origins of the Cybermen (audio story)"], Spare Parts [+]Loading...["Spare Parts (audio story)"], etc.) Indeed, in the midst of their confrontation with the Cybermen of a parallel Earth, the Tenth Doctor revealed to Rose Tyler that there were Cybermen in "[their] universe" who had "started on an ordinary world just like [Earth]" before "swarm[ing] across the galaxy". (TV: The Age of Steel [+]Loading...["The Age of Steel (TV story)"])
