The evil Doctor incarnation you mentioned was called the Valeyard, if he was a regeneration of the Doctor. I can't remember if it was explicitly stated that he was, or if it was just implied or something. (Also, minor note, while the name of the show is Doctor Who, the character is simply called the Doctor, not Doctor Who. I think the abbreviated form Dr was used in some of the credits in the early seasons, but they stopped doing that relatively quickly.)
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.