device, the Hand of Omega, to rework a nearby star into a new form to serve that source. Unfortunately, the star flared, first into a supernova, and then collapsed into a black hole. Omega was thought killed in that explosion but unknown to everyone, had somehow survived in an anti-matter universe beyond the black hole's singularity. Rassilon, the ultimate founder of Time Lord society, then took a singularity (assumed by fans and the spin-off media to be the same one as Omega's) and placed it beneath the Time Lords' citadel on Gallifrey. This perfectly balanced Eye of Harmony then served as the power source for their civilisation as well as their time machines. At some point in their history the Time Lords interacted with the civilisation of the planet Minyos, giving them advanced technology (including the ability to "regenerate" to a limited degree, by rejuvenating their bodies when they grow too old). This met with disastrous results, (which is said by some to be the reason the Time Lords adopted a philosophy of "non-interference"). The Minyans destroyed themselves in a series of nuclear wars. In "Dalek" (2005), the Ninth Doctor explains that his people perished along with the Dalek race in the "Last Great Time War", leaving the Doctor the last of his race. In "The Satan Pit" (2006), the Beast identifies the Tenth Doctor as "[t]he killer of his own kind." In "The Sound of Drums" (2007), the Master reveals he escaped the war by turning himself into a human following the Dalek Emperor taking control of the Cruciform. In "The End of Time" (2009–10), the Time Lords, after attempting to break out the time lock of the Time War and become creatures of consciousness, are shown being sent back into the War on the last day through the Tenth Doctor's intervention. The Master also disappears along with them. Rassilon describes Time Lord history in this story as having lasted "a billion years" up until the end of the Time War. In "The Day of the Doctor" (2013), thirteen incarnations of the Doctor are shown successfully attempting to freeze the Time Lords and their home world of Gallifrey in time, by transporting them to a "parallel pocket universe" using their TARDISes. Because the time streams are out of sync, the Doctor does not retain the memory of this until his eleventh incarnation. Indeed, earlier on in the episode, both