Black Dalek

Before the Last Great Time War, Black Daleks were senior ranking Daleks within the Dalek hierarchy and the most common rank to take up the role of Supreme Dalek, although this was not exclusive to their rank. (TV: Day of the Daleks, Planet of the Daleks) Those that did not hold the title of Dalek Supreme were subservient to the existing Supreme Dalek. (AUDIO: Brotherhood of the Daleks, Daleks Among Us) They outranked Silver or Grey Dalek drones, Blue Daleks and Red Daleks but were in turn outranked by Gold Daleks and the Dalek Emperor or the Dalek Prime. (PROSE: War of the Daleks)

Early History
The Black Dalek was summoned by the Dalek Emperor to deal with Zeg after he challenged the Emperor's authority. The Black Dalek's weapon was unable to penetrate Zeg's metalert casing. (COMIC: Duel of the Daleks)

When the Daleks developed space travel, the Emperor led an invasion force off Skaro to conquer other planets, (COMIC: The Amaryll Challenge) leaving the Black Dalek in charge of the Dalek City. When the Daleks were threatened by the outbreak of a rust plague, the Black Dalek was infected in such as way that it could be used as a vessel to transmit the plague to other Daleks. The Emperor returned to Skaro to deal with the situation and found the Black Dalek rusting away, resigned to its fate. The Emperor claimed the Black Dalek was too valuable to lose and sent it to the recasting furnace to be repaired. (COMIC: Plague of Death)

Later, after its recovery, the Black Dalek led a force of Daleks to the planet Phryne in search of new technologies as war with the Mechanoids became evermore certain. They successfully occupied the planet. (COMIC: The Archives of Phryne)

Expansion of the Dalek Empire
The invasion of Earth in the 22nd century was commanded by a Black Dalek with the title of Supreme Controller. It was killed when the Bedfordshire mine exploded and the invasion failed in 2167. (TV: The Dalek Invasion of Earth)

After the failure of the invasion, the Daleks identified the Doctor and a Black Dalek, under orders from the Dalek Prime, (PROSE: The Chase) ordered an assassination squad to pursue his TARDIS in a Dalek time machine. The squad failed. (TV: The Chase)

Another Black Dalek acting as a Supreme Dalek oversaw the Dalek operations on planet Kembel in the year 4000. It was wiped out when the Doctor hijacked the Time Destructor. (TV: Mission to the Unknown/The Dalek's Master Plan) This was a massive blow for the Dalek Empire as the Dalek Prime considered both the fleet and the Black Dalek irreplaceable. (PROSE: The Mutation of Time)

A Gold Dalek acted as the Supreme Dalek in an alternative timeline in which the Daleks reconquered 22nd century Earth but according to one account, a Black Dalek was also present, acting as the Gold Dalek's second-in-command. (PROSE: Day of the Daleks)

The Imperial-Renegade Dalek Civil War
At the beginning of the civil war between the Imperial Daleks and the Renegade Daleks, another Black Supreme Dalek led the expedition to find Davros and have him develop a cure for the Movellan virus. Stien, a rouge Dalek Duplicate, set the space station to self-destruct and the Black Dalek was one of many resulting Dalek casualties. (TV: Resurrection of the Daleks)

Black Daleks lead Dalek assault forces or operations, including the invasion of Gallifrey, (AUDIO: The Apocalypse Element) capturing the Sixth Doctor to prevent Davros from building the Juggernauts, (AUDIO: The Juggernauts) and the attack on Bliss. Black Daleks could self-destruct with such power to destroy a base. (AUDIO: Enemy of the Daleks)

During the Shoreditch Incident, the Renegade Daleks were commanded by a Black Dalek. It was the last remaining Dalek of the incident and killed itself after the Seventh Doctor convinced it it had no purpose. (TV: Remembrance of the Daleks)

After the end of the Imperial-Renegade Dalek Civil War, forces within the Dalek Empire were divided on who to support - Davros or the Dalek Prime. Only the Gold Daleks remained fully loyal to the Dalek Prime while the Black Daleks, along with the Red Daleks, Blue Daleks and drone units, were split. The Dalek Prime organised for Davros to be placed on trial in hopes his supporters would reveal themselves and this proved successful as a Black Dalek attempted to assassinate the Dalek Prime before Davros could be executed. Davros's supporters were believed to have been destroyed in the ensuing battle. (PROSE: War of the Daleks)

The Time War and later history
During the Last Great Time War, Black Daleks were among many ranks of Daleks and Skaro Degradations present at a temporary base on Moldox in the city of Andor. They were overcome in a prisoner revolt insitgated by the War Doctor and Cinder. (PROSE: Engines of War)

When the Daleks of the New Dalek Paradigm reintroduced the bronze casings previously used in the Second Dalek War and the Last Great Time War, (TV: Asylum of the Daleks) Black Daleks were also reintroduced as lower-ranking officers. One such Dalek oversaw the progression of the Dalek Project before its destruction in a battle of the First World War. (COMIC: The Dalek Project)

Other Black Daleks
Davros's chair, on which the Dalek design was partially based, was black. (TV: Genesis of the Daleks)

A Dalek working in a Dalek Test Chamber had a casing which alternated between black and white. (COMIC: Eve of War)

Dalek Saucer Commanders which oversaw saucer operations during the invasion of Earth had a casing which alternated between black and silver. (TV: The Dalek Invasion of Earth, COMIC: The Threat from Beneath)

The Dalek Emperor's guards and other elite guards had black domes and were even referred to as Black Daleks. (TV: The Evil of the Daleks, The Parting of the Ways, PROSE: Prisoner of the Daleks, GAME: The Eternity Clock)

A half black, half gold Dalek arrived on Spiridon on the eve of the Second Dalek War and was said to believed by the Thals to be a member of the Supreme Council. (TV: Planet of the Daleks) Another such Dalek, the immediate subordinate to the Emperor, was part of a mission on Kar-Charrat to obtain information from the planet's Library. (AUDIO: The Genocide Machine)

During the Second Dalek War, Dalek X, the Dalek Inquisitor General, had a gunmetal black casing decorated with gold. (PROSE: Prisoner of the Daleks)

Dalek Sec, the leader of the Cult of Skaro, could be easily identified by his distinctive solid black casing prior to his evolution into a Human-Dalek hybrid. (PROSE: Birth of a Legend, TV: Army of Ghosts/Doomsday, Daleks in Manhattan/Evolution of the Daleks)

Behind the Scenes

 * In both Dr. Who and the Daleks, the remake of The Daleks which itself did not feature a Black Dalek, and Daleks' Invasion Earth 2150 A.D., the remake of The Dalek Invasion of Earth, a Black Dalek is present.
 * Black Daleks have featured much less prominently in revived series media than in classic series media. It was not until The Dalek Project in 2012 that a Black Dalek was seen again as a rank, Dalek Sec and Dalek X before it being individuals with a unique position rather than a shared rank. 2014's Engines of War followed this up by including some Daleks with black casings, though only briefly.