Known multiverses (The Infernal Nexus)
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Station Control was a nexus between 417 multiverses, referred to by locals as the known multiverses. All of these multiverses existed in radically different states, having different rules for their own internal functionings as multiverses. Rather than existing outside the universe, these multiverses existed within it in a complicated manner which only Rupert Gilhooly could come close to understanding, with there definitionally only being one universe.
These included the Infernal Regions. (PROSE: The Infernal Nexus [+]Loading...["The Infernal Nexus (novel)"])