In 2163 when he and Peri Brown arrived on Earth, a year before his original incarnation arrived to stop the Dalek Invasion, the Sixth Doctor was taken to be interrogated by a Black Dalek, distinct from the Supreme Controller. It tortured him into revealing his identity and how he knew so much about the Daleks, but in order to prevent the Daleks' defeat from being reversed in a year in the future, he refused. It explained that the Robomen Elite were more independent and distinctive from the others as they could adapt human emotions in order to infiltrate resistance groups. When the Doctor mentioned the mines in Bedfordshire, it demanded to know he knew of this. Again, the Doctor dismissed the question. It, along with the other Daleks, were killed by the Varga Virus, released by Moira Brody. (AUDIO: Masters of Earth)
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