trigger his regeneration into a new form, but allow him to choose which characteristics his next incarnation will have. They convince the Doctor that he must take action to end the Time War, which "threatens all reality". The Doctor's initial rejection is met by the response that he is "dead already; how many more will you let join you?", and the Sisters beg him not to allow the universe to fall, as it presently "stands on the brink". The Doctor acknowledges there is not much need for a doctor any more, salutes the memory of his past companions, and asks for a potion that will turn him into "a warrior". He utters his last words ("Physician, heal thyself") and, after drinking it, regenerates into a new incarnation, known as the War Doctor (John Hurt), who declares, "Doctor no more." Karn and Ohila, the head of the Sisterhood, reappear in the 2015 mini-prologue to the Twelfth Doctor story "The Magician's Apprentice". Ohila tells the Doctor that someone is searching for him. The Doctor states he will confront his pursuer and gives Ohila his "confession dial" – a Time Lord's last will and testament – knowing she knows whom to deliver it to. Karn and the Sisterhood also appear, hiding the Doctor, in the broadcast episode itself. Davros' agent Colony Sarff tries to attack the Sisterhood, but his powers are neutralised on Karn, and he retreats. When the Doctor returns to Gallifrey in "Hell Bent", the Sisterhood appear unannounced in the High Council of Gallifrey's chamber to tell Rassilon (Donald Sumpter) that the Doctor blames only him for the horrors of the Time War. Ohila is dismayed as the Doctor flees Gallifrey with his companion Clara (Jenna Coleman) in an attempt to cheat her death. Audio dramas The Sisterhood of Karn also feature in the Big Finish Productions audio dramas Zagreus and the two-part story Sisters of the Flame/Vengeance of Morbius. References Doctor Who organisations