Doctor Who: 10 Worst Things That Have Happened To The Doctor At Christmas
5. Fighting In A Centuries-Long War
While most of the Doctor's festive outings take place within a short amount of time, the 2013 Christmas special was a long day at the office for the Eleventh Doctor.
After being drawn to a message emanating from a planet called Trenzalore, the Doctor finds himself engaging in a centuries-long conflict against countless alien foes, all of whom have also been drawn to that same message. At one point, the Doctor says that "half the universe" is present, including the likes of the Daleks, the Cybermen, the Sontarans, the Weeping Angels, the Terileptils, the Slitheen, and the Silurians. Yikes.
This gives the Doctor a big ol' problem to deal with, and in order to protect the innocent residents of a local town called Christmas, he takes it upon himself to repel these alien invaders, leading to that aforementioned centuries-long conflict.
Along the way, the Doctor grows old and weary, he loses people, and he has to stay on his toes constantly, due to the fact that several of his enemies end up getting rather creative with their attempts at breaching the town. This was a truly noble act on the Doctor's part, and overall, defending Trenzalore was easily one of the most difficult things he's ever done.