Grey Dalek

Grey Daleks (PROSE: Remembrance of the Daleks) were basic Daleks with dark gray casings, who served as the default form of Dalek drone at many points in the Daleks' history, beginning with the first Mark III Travel Machines unveiled by Davros. (TV: Genesis of the Daleks)

Though the first Daleks on Skaro's casings were the slatless, pale Dalek War Machines, (TV: The Daleks, COMIC: Genesis of Evil, Legacy of Yesteryear, etc.), later phased out in favor of Silver Daleks slightly more similar to Davros's Grey Daleks, (TV: The Chase, The Evil of the Daleks, COMIC: Shadow of Humanity, etc.) Grey Daleks served as the default Dalek drones throughout the bulk of the Daleks' history prior to the Last Great Time War. (TV: Destiny of the Daleks et al.) During the Imperial-Renegade Dalek Civil War, they were classed as Renegade Daleks, loyal to the Supreme Dalek and Dalek Prime and opposed to the white Imperial Daleks loyal to Davros. (TV: Remembrance of the Daleks)

Hierarchy
The grey Daleks were subordinate to Gold Daleks, (TV: Day of the Daleks) Black Daleks, (TV: Resurrection of the Daleks) and black-and-gold Supreme Daleks of the Supreme Council. (TV: Planet of the Daleks)

Though generally appearing as foot soldiers, grey Daleks could also be of higher ranks. On Spiridon, a grey Dalek served as Section Leader. (TV: Planet of the Daleks)

Variants
The first Mark III Travel Machines presented by Davros were grey casings with grey slats and black sense globes, with blue rings across the Dalek eyestalk. (TV: Genesis of the Daleks) Later Daleks, seen during the Dalek-Movellan War, had black slats as well as sense globes. However, grey-slatted Daleks remained during this time, and appeared to serve as leaders to the black-slatted Daleks. (TV: Destiny of the Daleks)

The grey Daleks that rescued Davros from the Prison Station had black slats and sense globes. However, the rings across their eyestalks were white rather than blue. They were subordinate to a black Supreme Dalek with white sense globes. (TV: Resurrection of the Daleks) Identical Daleks later came to Necros to capture Davros. (TV: Revelation of the Daleks)

Davros's first creations
On Skaro, in the account of the creation of the Daleks which saw them as the creations of the scientist Davros, the first Mark III Travel Machines which Davros presented to the Kaled Scientific Elite were dark grey. The newly-christened Daleks were sent by Davros to exterminate the Thals, supposedly in retaliation for the attack on the Kaled Dome. They turned on Davros, as they were not programmed to recognise any creature as superior to them, apparently killing him. Accidentally, whilst attempting to stop the Fourth Doctor, a Dalek triggered an explosion which destroyed the embryo room before the Thals sealed the bunker entrance and trapped the Daleks there. In the aftermath, the Doctor believed he had only held back their progress by about a thousand years or so, and that they would return. (TV: Genesis of the Daleks) Following his encounter with Grey Daleks, a Grey Dalek was among the foes whom the Fourth Doctor saw call out to him in his mind shortly before his fall from the Pharos Project radio telescope, which resulted in his regeneration to his next incarnation. (TV: Logopolis)

Use as the basic Dalek drones
After the Dalek Empire spent some time with Machine Daleks, and then Silver Daleks, as its default drones, (TV: The Daleks, The Evil of the Daleks) Grey Daleks resurfaced when, led by a Gold Dalek, a group of them invaded Earth in an alternate 22nd century after the World Peace Conference was destroyed by Shura from the future. World War III started as various global factions accused each other of having done so. They used Ogrons as enforcers. The Third Doctor and Jo Grant travelled to 1970s and undid that alternate timeline. Shura used the bomb to destroy the Daleks and Ogrons in the Auderly House. (TV: Day of the Daleks) One account claims a Black Dalek was present as a second-in-command and was responsible for much of the Gold Dalek's tasks while the Gold Dalek acted as an overseer. (PROSE: Doctor Who and the Day of the Daleks)

The Daleks allied with to undermine the Earth and Draconian Empires and set them against each other and then take over with a huge army assembled on Spiridon. (TV: Frontier in Space) Despite the Master's failure to cause war, the army was prepared and the Daleks looked toward utilising the invisibility properties of Spiridon's inhabitants as a means of developing stealth technology. However, all of these plans were foiled when the grey Dalek army was frozen by the Third Doctor and a taskforce of Thals. (TV: Planet of the Daleks)

Grey Daleks fought in a war against the Movellans, (TV: Destiny of the Daleks) as did later Bronze Daleks. (TV: The Pilot) The conflict soon resulted in a stalemate: each side's purely logical battle computer kept them in deadlock. To circumvent this stalemate, the Daleks returned to Skaro to find Davros so his biological mind could reprogram their battle computers to win the war. However, the Fourth Doctor defeated them and the Movellans and Davros was taken by the Daleks' former slaves to stand trial. (TV: Destiny of the Daleks) The war continued for another 90 years, until the Movellans developed a Movellan virus to defeat the Daleks. (TV: Resurrection of the Daleks) During the course of this conflict, some of the first Bronze Daleks were also deployed. (TV: The Pilot)

A grey Dalek was time scooped to the Death Zone on Gallifrey, where it tried to exterminate the First Doctor and Susan Foreman, only to be destroyed when they pushed it into a dead end, causing its energy weapon to ricochet and destroy it. (TV: The Five Doctors)

Renegades versus Imperials
A detachment of grey Daleks led by a black Supreme Dalek went to free their creator to find a cure for the Movellan virus. They also used a time corridor and a Dalek duplicate called Stien to trap the Fifth Doctor to duplicate him and his Companions to assassinate the Time Lord High Council. However, the Doctor broke free of the duplication apparatus and turned Stien to his cause. Meanwhile, Davros turned several Dalek Troopers and two Daleks to his cause but the Supreme's Daleks destroyed the rebels. Both Davros and the Doctor unleashed the virus and the Dalek ship was destroyed by Stien. (TV: Resurrection of the Daleks)

Davros escaped to Necros and began to turn intelligent cryogenically frozen people into Imperial Daleks to conquer the universe. However, Takis called the Renegade Daleks to take Davros to stand trial. The Renegades fought their way past the Imperials to take Davros. He tried to get them to take the Sixth Doctor, but they did not recognise him. The Renegades' attempt to recondition the Imperials failed because of the Imperials' destruction by the Doctor and Orcini. (TV: Revelation of the Daleks)

The Renegade and Imperial Daleks both headed to Earth in 1963 to claim the Hand of Omega, waging a lengthy battle at Shoreditch. Aided by the Special Weapons Dalek, the Imperial Daleks won, almost wiping out the Renegades aside from the Supreme, who later self-destructed after the Seventh Doctor manipulated the Imperials into destroying Skaro. (TV: Remembrance of the Daleks)

Encounters the Eighth Doctor
In a vision of his future, the Eighth Doctor saw "a conical robot, gunmetal-grey" which swung a camera eye at him with the lights on the top of its head flashing angrily. (PROSE: Father Time)

Looking into his future via the Tomorrow Window, the Eighth Doctor saw "squat machines in gunmetal grey" gliding through the rubble of a ruined city beneath a flying saucer, their eyestalks scanning from left to right. (PROSE: The Tomorrow Windows)

Phasing out
Bronze Daleks, such as were already deployed in the late stages of the Dalek-Movellan War, (TV: The Pilot) eventually supplanted the Dalek drones as the default casing used by Dalek drones, in the time leading up to and during the Last Great Time War. (TV: Dalek, The Day of the Doctor) The varyingly-successful attempts by the Daleks post-War to rebuild their power base also employed Bronze Dalek casings, such as the Dalek Emperor's half-human Dalek Fleet (TV: The Parting of the Ways) or the New Dalek Empire. (TV: The Stolen Earth) Even after the New Dalek Paradigm attempted to introduce red Drone Daleks, (TV: Victory of the Daleks) Bronze Daleks would endure. (TV: Asylum of the Daleks, Into the Dalek)

Some Grey Daleks did remain in the universe after their casing type was replaced by the Bronze ones, however. Some Grey Daleks, having survived encounters with the Doctor and classed as insane, had been taken to the Dalek Asylum. These insane Daleks died when the asylum was destroyed by the Parliament of the Daleks. (TV: Asylum of the Daleks)