The Silver Devastation was an area of space in the Isop Galaxy where two galaxies collided some hundred billion years ago. This vast sector of space contained nothing but dead stars and dark matter. From a great distance it looked like a huge silver sea hanging in space, the edge area being commonly referred to as its "coast". (PROSE: The Game of Death)
Behind the scenes edit
Russell T Davies stated on the Utopia DVD box set commentary that Yana's memories were true. Davies said of this backstory: "He was a baby. A human baby. Because that's what the Master did — he was so frightened and terrified that he wiped himself as a baby and found on the Silver Devastation."