Grandfather Paradox

Grandfather Paradox was the nominal leader of Faction Paradox.

Biography
The speaker's chair in the Eleven-Day Empire was left vacant to be taken by the Grandfather upon his appearance to the Faction Paradox. (EDA: Interference - Book One) The Faction Paradox held the Grandfather Paradox up as one of the ultimate forms of temporal paradox.

According to Faction Paradox legend, the Grandfather Paradox had one arm. He had removed this arm to remove the Time Lord branding/tattoo of a prisoner, and he would have committed the ultimate paradox.

Resulting from a corrupted timeline, from Faction Paradox corrupted biodata, a future version of the Eighth Doctor modelled himself as the Grandfather Paradox. (EDA: The Ancestor Cell). Other accounts suggest that Grandfather Paradox appears as a twisted, morally bankrupt and broken version of whoever is looking at him or "the ghost of Christmas cancelled" as the Doctor snidely put it. (EDA: The Gallifrey Chronicles) However, if the Doctor was indeed the true Grandfather Paradox, then this version had indeed committed the ultimate paradox; he cut off his arm not to remove the Time Lord branding/tattoo, but because he knew it was the arm which the Doctor would use to destroy Gallifrey. (EDA: The Ancestor Cell)

Behind the scenes

 * The name Grandfather Paradox punningly refers to from theoretical science and science fiction.
 * This character's history was substantially revised for use in the . Despite the common names, readers of FPU material will notice differences between the two versions.  Markedly, there is no suggestion that the FPU version of the Grandfather is the Doctor.