Cloister Wars
From Tardis Wiki, the free Doctor Who reference
The Cloister Wars were a series of conflicts mentioned by Missy to Clara Oswald when explaining how long she had cared for the Doctor. She also mentioned "the night he stole the moon and the President's wife", and that it had also been so long "since he was a little girl". She then stated that one was a lie, and asked Clara if she could tell which one. (TV: The Magician's Apprentice)