Skaro City Dalek (Dr. Who and the Daleks)

From "film evidence", the Dalek Survival Guide identified an alternative model of Skaro City Dalek which populated the Dalek City on Skaro. These Blue Daleks followed a red Dalek Lieutenant and a black Dalek Leader and were defeated in battle with the Thals assisted by Dr. Who, (PROSE: Dalek Survival Guide, TV: Dr. Who and the Daleks) who went on to thwart the 2150 Dalek invasion of Earth in a "version of history B" relative to the First Doctor's "version of history A". (TV: Daleks' Invasion Earth 2150 A.D., PROSE: Dalek Survival Guide)

Characteristics
The Skaro City Daleks operated casings mostly coloured pale blue in the middle section and lower section, with a dark blue dome section and sensor globes of the lower section. The neck rings which supported its black neck grille were also a pale blue, whilst the shoulder rings atop and below the arm sockets were gold, and the tall fender at the bottom of the lower section was dark blue. The eyestalk that connected the eye lens, which appeared as a shining white disc at the face of a black ball, to the dome's pivot and the six insulator discs that supported it, were coloured silver and light blue respectively. The left arm of the middle section was a gunstick, while the right arm alternated between claw manipulator arms and sucker arms. Two red, cone-shaped luminosity dischargers stood atop the dome and flashed when the Dalek spoke. (TV: Dr. Who and the Daleks)

History
As reported by the Space News Agency on 26 June 2065, the Red Dalek and the Black Dalek participated in the planning of the Dalek invasion of Alvega in the control room of the Dalek City on Skaro. The War Machine Dalek drones under their command were coloured blue. (PROSE: Daleks Seek New Conquests) Identical blue Daleks were seen at Dalek Tracking station PZ8 before it fell to the rust plague. (PROSE: Daleks Suffer Heavy Losses!)