Janizzar was a vault-world used by the Shadow Proclamation, which an agent of the Cybock Imperium described as "the most impregnable world in the universe".
In 1963 the Cybock Imperium attacked the planet and stole the Time-Gun of Rassilon from within its vaults. The Judoon attempted to stop the thief, but were wiped from history when the time-gun was used. (COMIC: Gangland)