Vision Disruptor

The Vision Disruptor was a "gizmo" created by the Eleventh Doctor in the city of Kaalann on Skaro using the Dalek Visualiser along with a Dalek eyepiece and gunstick taken from the Production Facility by Amy Pond. Though the device by itself had only a limited range, this was increased when Amy fitted it into the cradle of the old Emperor, disabling the vision of all Daleks in the Supreme Council Chamber and allowing the Doctor to free the Eye of Time, averting the Daleks' altered timeline. (GAME: City of the Daleks)