Final days of the Time War

The Tenth Doctor recalled the "final days" of the Time War between the Time Lords and the Daleks, (TV: The End of Time) although those alive in the conflict were faced with the fact that recognisable days no longer existed. (AUDIO: Day of the Master)

A Time Lord historian noted that Rassilon's final High Council stood during the "last days of the Time War", including the Partisan, the Visionary and the Woman. (PROSE: A Brief History of Time Lords)

The Doctor understood that the Master was not present for the final days of the War and so did not see "what was born" as the War turned into "hell", (TV: The End of Time) since the War Master had fled the conflict in fear when the Dalek Emperor seized control of the Cruciform, (TV: The Sound of Drums) an unintended consequence of the Master's use of the Heavenly Paradigm. (AUDIO: The Heavenly Paradigm) According to another account, the Tenth Doctor said that the Cruciform fell at the same time that Gallifrey was burned. (COMIC: The Forgotten)

The Doctor warned that, had the time lock been broken on the Final Day, then it would unleashed upon the universe not only the Daleks but the Skaro Degradations, the Horde of Travesties, the Could've Been King with his Army of Meanwhiles and Neverweres, and the Nightmare Child (TV: The End of Time) the latter of which he saw Davros's command ship fall to in the first year of the Time War. (TV: The Stolen Earth) As the Final Sanction planned by Rassilon's High Council would have done just that, the War Doctor was motivated to use the Moment to end the War. (TV: The End of Time)

Human historians in the post-Time War universe understood that the Cult of Skaro had developed the Void Ship known as the Sphere during the final days of the Time War, and that they had used it to escape into the Void along with the Genesis Ark during the "final moments" of the conflict. (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe)

The Time Lords of Gallifrey foresaw that their own destruction would come in the "last day of the Time War", also known as the Final Day, (TV: The End of Time) only for all incarnations of the Doctor to relocate the planet to a parallel pocket universe. (TV: The Day of the Doctor) The Eleventh Doctor would later admit to himself that millions of days along his timeline were the last day of the Time War. (PROSE: The Day of the Doctor)

Behind the scenes

 * The publisher's summary for the novelisation of The Day of the Doctor establishes the Time War's "dark days" to be its final days, describing the War Doctor fighting Daleks during the time.