The Last Great Time War
*The Last Great Time War takes place between the 1996 Doctor Who tv-movie and the 2005 revival, continuation of the series*
The Start
The Last Great Time War started as an act of revenge by the Daleks. The Daleks had a goal to destroy all life forms in the universe, which still if their main goal which The Doctor effectively prevents to date. As the Time Lords see a possibility that the Daleks may reach this goal, they decide to take action. Their plan was to send the (4th Doctor) Doctor back in time to stop or delay the creation of the Daleks. With the failure of the plan, and the Daleks knowledge of the attempt, The Last Great Time War began. The Time Lords fought against the Daleks "for the sake of all creation" (10th Doctor).
The End
Nearing the end of the war, The Doctor, currently in the War Doctor regeneration of himself, realized that the war was turning to hell. It was no longer just the Daleks, but the Skaro Degradations, the Horde of Travesties, the Nightmare Child, and the Could've Been King with his Army of Meanwhiles and Neverweres (10th Doctor). With the Doctor seeing the Time Lords perfecting ways to kill life and no end the the war, he saw no choice but to end it all. He intended to use The Moment to do so. The Moment was invented by the Time Lord, and it could wipe out Gallifrey and the Daleks in a single moment, hence its name. This made it so The Doctor had supposedly burned all the combatants of the Time War and were they "wiped out in one second" (9th Doctor), leaving Doctor as the last Time Lord and to live with the burden of this.
The Doctor's Memories Were Wrong
Once the 2005 revival of the series began, it was evident that some of the Daleks had survived. With this began The Doctors realization that his reality of what he had done might not be true, although he still believed that he has killed all of his people. He held this belief until his timeline had caught up the 11th Doctor. The 9th, 10th, and 11th Doctor did not want to be associated with the War Doctor, so they had referred to him as "the one that broke the promise". Brought back to the time of The Moment being used by the War Doctor, The Moment had revealed that it developed its own conscience that could read the mind and timeline of the one that intends to use it. Looking into The Doctors time The Moment took the form of Bad Wolf, aka Rose Tyler. The Moment gave the War Doctor the chance to change the course of the war with help of the 10th and 11th regenerations. As they all prepared to help the War Doctor to push the button to detonate The Moment, Clara told the 11th Doctor to remember his vow as The Doctor, so he deactivated The Moment. Together, with the help of his previous regenerations and the 12th Doctor, they find a way to freeze Gallifrey in time. This meant that Gallifrey and the Daleks still vanished, but they were just stuck in a pocket in the universe that was stuck in a time-loop.
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