Time Lord Victorious

Time Lord Victorious was a title the Tenth Doctor briefly claimed due to his status as the terminator, final survivor, and "winner" of the Last Great Time War.

A day to come
When the Fourth Doctor encountered a damaged Dalek Drone on the Starship Future, it told him that one of his future selves would turn into everything he opposed and become the Time Lord Victorious. The Doctor refused to believe it, however it teased him that “Out of any good must come something evil”. (AUDIO: Genetics of the Daleks)

Claiming the title
During his visit to Bowie Base One in 2059, the Tenth Doctor realised that, as the last of the Time Lords, he had control over the Laws of Time. He demonstrated this by breaking a fixed point in time to rescue Adelaide Brooke, Mia Bennett, and Yuri Kerenski. In a subsequent conversation with Adelaide, he confirmed her suggestions that he was effectively omnipotent and unstoppable; she decried the implications of his actions. (TV: The Waters of Mars)

"This is wrong, Doctor. I don't care who you are. The Time Lord Victorious is wrong."

- Adelaide Brooke

Following Adelaide's vehement rebuke and subsequent suicide, the Tenth Doctor returned to the TARDIS, pondering omens of his regeneration. (TV: The Waters of Mars) The change to history had created a Time Fracture (PROSE: What the TARDIS thought of "Time Lord Victorious") which the Doctor used to flee to the Dark Times. There, he seized the opportunity to interfere with the Kotturuh crisis and end death by infecting the Kotturuh with a modified version of their own infection, believing he could completely rewrite history for the better. After unleashing it on the Kotturuh on Andalia, he again declared himself the Time Lord Victorious, claiming that his word was eternal.

Dismissing his internal concerns that he wasn't doing the right thing, the Doctor led the Victis Fleet to finish the Kotturuh by destroying their planet Mordeela and seal off their power source. However, he was interrupted by two of his prior incarnations, the Eighth and Ninth Doctors, allied with the Dalek Time Squad and Vampires. (PROSE: The Knight, The Fool and The Dead) The Tenth Doctor refused to back down and ordered his fleet to fire, destroying the planet. This began the Battle of Mordeela, resulting in the destruction of the Tenth Doctor’s fleet except his ship. In the damage he reflected that the Time Lord Victorious had been beaten, but Brian encouraged him. He managed to use Mordeela’s ruins to seal the gateway to the Kotturuh’s power source as intended and used that as a distraction to enable his ship to escape. (PROSE: All Flesh is Grass)

Afterwards the Doctor continued harbour doubts about what he’d done, seeking the Minds of Magnox for an answer about whether he was in the right. When a Kotturuh ship laid waste to Magnox after Brian killed the Minds, thus depriving them of the chance to ask how to defeat the Doctor and survive his death sentence, the Doctor helped a few Magnoxians flee to Islos. He was rebuked by Peschell for having brought the Kotturuh down on them, with her horrified by him offering to let her travel with him. Though solemn, the Doctor insisted to Brian that he had to continue his war as the Time Lord Victorious. (AUDIO: The Minds of Magnox)

The Doctor eventually came to regret his actions after meeting Inyit, the last of the Kotturuh, who revealed the Kotturh weren’t what they’d appeared to be. However he suggested the Eighth Doctor taunt the Daleks with the title when he detonated an explosive aboard their saucer during the Defence of Gallifrey, with the ensuing explosion forcing the Dalek ship out of the Dark Times. Afterwards he agreed with the Ninth Doctor not to alter history any further, effectively relinquishing the title. (PROSE: All Flesh is Grass)

Alternate timeline
In an alternate timeline, rather than exposing himself to lethal radiation to rescue Wilfred Mott at Joshua Naismith's mansion, the Tenth Doctor judged his life to be more important and left Wilf to die. He reclaimed the "Time Lord Victorious" title and became emperor of the universe, demanding tributes from ambassadors from across the universe to help feed the starving. He was ultimately assassinated by a Raxacoricofallapatorian. The Tenth, Eleventh, and Twelfth Doctors witnessed these events after they were caught in the explosion of a Dalek continuity bomb. (COMIC: Four Doctors)

Behind the scenes

 * The alternate timeline where the Doctor becomes Emperor of the universe before being assassinated closely resembles the story of the Emperor from the novel Father Time, who was revealed in The Gallifrey Chronicles to be a future incarnation of the Eighth Doctor.
 * At VividCon 2008, a fan video debuted which juxtaposed shots from series 2, 3, and 4 episodes with the Flobots song "Handlebars", suggesting that the superficially carefree and easy-going Tenth Doctor was descending into increasingly dark and destructive actions. Writer Paul Cornell praised the video's character study as "brilliant and shocking". In homage to the video, the Tenth Doctor's subsequent turn to Time Lord Victorious in The Waters of Mars has been described by some fans and writers as going "full handlebars".