Time's Champion
Time's Champion was a title used by various individuals, most notably the Seventh Doctor, after making a deal with the Menti Celesti Time. (PROSE: Love and War, Original Sin, et al.) It signified a responsibility to protect history, no matter the cost. (PROSE: Christmas on a Rational Planet)
During the Sixth Doctor's lifetime, Time was looking for a champion to make the difficult decisions needed to save time and space from a coming conflict. The Valeyard told the Sixth Doctor that he planned on applying. (PROSE: Millennial Rites) Elektra and Prometheus hoped their child, Kronos, would become Time's Champion. (PROSE: The Quantum Archangel) Ultimately, the Seventh Doctor agreed to become Time's Champion. As payment, he sacrificed his prior incarnation. (PROSE: Timewyrm: Revelation, Love and War)
To protect history, the Doctor set a complex array of plots and counterplots into motion. He and his companions would often became trapped in his own schemes, relying on his future self to arrange things so they would turn out right. (PROSE: No Future) These designs would often involve the Doctor's companions without their knowledge or consent, placing them in harm's way. (PROSE: Love and War, Head Games) Ace notably rebuked the Doctor for sacrificing Jan Rydd as part of a plan to stop the Hoothi. (PROSE: Love and War) The Doctor struggled with his culpability for these deaths; he started sleeping less to avoid nightmares (PROSE: Head Games) of the Sixth Doctor's voice taunting him. (PROSE: Return of the Living Dad, Head Games) In response to one of these dreams, he remarked, "I am Time's Champion, and guilt is a luxury I can no longer afford!" (PROSE: Head Games)
At different times, the Doctor was addressed with the title by the Hoothi, the Puterspace, (PROSE: Love and War) the Grandmaster gestalt, (PROSE: So Vile a Sin) and the Carnival Queen. (PROSE: Christmas on a Rational Planet) Iris Wildthyme laughed in the Doctor's face when he said he was Time's Champion. (PROSE: The Scarlet Empress, The Blue Angel) When Time appeared to Kadiatu Lethbridge-Stewart, she directly named the Doctor as her champion. (PROSE: Set Piece)
After Roz Forrester's death, the Doctor felt ready to abandon the Champion role by regenerating. (PROSE: The Room With No Doors) The Eighth Doctor included "Champion of Time and Life" among his titles when repelling the Ice Warrior invasion of the United Kingdom, (PROSE: The Dying Days) but later grew to regret his past incarnation's actions. (PROSE: The Blue Angel, et al.)
Other claimants to the title included Iris Wildthyme, Daedalus, (PROSE: The Blue Angel) and Sabbath. (PROSE: Camera Obscura, The Domino Effect)