Faction Paradox invasion of Gallifrey

Following the growing infection in the timeline caused by the Third Doctor regenerating on Dust rather than Metebelis III, the War was prematurely ended when the Eighth Doctor destroyed Gallifrey in order to prevent Mother Mathara and her Faction, and his future fallen self having control over the Web of Time.

Origins
Following a brief encounter with the future Eighth Doctor, the Third Doctor landed on Dust, rather than Metebelis III. This resulted in him interacting with a splinter of Faction Paradox who were there, including his future ex-companion Father Kreiner (previously Fitz Kreiner), and eventually getting shot and regenerating, consuming the Facttoin's nearby biodata virus. Before regenerating, he said "a tear, Sarah Jane?", the beggining of his last words in the correct timeline, but ended on "this is wrong", before regenerating into the Fourth Doctor.

Mother Mathara explained to Cousin Llewis that the Third Doctor would "regenerate into the same form he was scheduled to regenerate into", and that in general, "history would carry out much as before, apart from [this] one alteration". (PROSE: ) However, according to one account, the effects of the changed timeline on Dust caused a major paradox in the continuum, resulting in the version of the Doctor's TARDIS which was present on Dust, along with its occupying Third Doctor, being pulled off-causality and becoming the Edifice and a ghost of the Third Doctor, respectively, and eventually arriving on a version of Gallifrey and sending "temporal waves" over it, upsetting the established future course of events. (PROSE: )

However, one account held the situation to be slighly more complex. According to this account, the Mother Mathara present during the Faction Paradox invasion of Gallifrey was, in fact, from a point in the War beyond its 50th year, having exploited the "Trojan Horse" - the infected timeline, specifically the "infected agent"- to travel backwards in Homeworld time. The version of the Faction lead by Mathara was said to be quite different from the earlier form, founded by the Grandfather of House Paradox - this included the fact that Mathara's Faction was overtly sadistic, and also that quite a few of her members were practically cadavers, rather than simply employing death imagery. (PROSE: )

Invasion
Arriving on Gallifrey (PROSE: ) from beyond the War's 50th year through exploiting the large "crack" in casualty caused by the infected timeline, (PROSE: ) known as the Edifice. Once on Gallifrey, Mathara hid in the body of a female Time Lord until she had amassed a cult of enough strength to resurrect Greyjan the Sane, whom they called the "Sage of Paradox". (PROSE: ) Additionally, and through unknown methods, Mathara's Faction managed to bring back the "ancient horrors from the dawn of time" that scared the 406th President, tricking the whole High Council into believing they are their foreseen enemy.(PROSE: The Capitol is then overthrown in the chaos, and transformed into a new Eleven-Day Empire.(PROSE:, ) An "ersatz" (PROSE:  Grandfather Paradox, who was none other than a future version of the Eighth Doctor,(PROSE: ) was then placed on Lady President Romana III's throne. (PROSE:, )

The Eighth Doctor, deciding he'd rather see his homeworld fall then let the Faction reign, made his way to the Edifice, wherein he and Grandfather Paradox confronted each other. During this confrontation, Grandfather Paradox murdered Father Kreiner just as he was starting to trust the Doctor again. Finally, the Doctor pulled down a lever in the Edifice which resulted in it overpowering and blowing up the whole of Kasterborous, including Mathara's warships. This appeared to not only avert the future War the Eighth Doctor had previously interacted with, but also all of Gallifreyan history, including the founding of Faction Paradox - who were said to have been "erased for ever" -, (PROSE: ) resulting in a new form of reality where history was "fundamentally altered". (PROSE:

However, one account stated that rather than the Eighth Doctor having ended the War, instead he just "fell from the Warring Heaven". (PROSE: )

Legacy
On one occasion, the Tenth Doctor looked back on his destruction of Gallifrey at the end of the Time War, depicted as the memory of the Eighth Doctor during this invasion. (PROSE: )

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