The Dominators were a group made up of the male half of a race of humanoids from Drahb. A gang of conquerors, they claimed to control much of the Ten Galaxies. They were intensely utilitarian, and hesitant to misuse any amount of energy for matters that did not directly benefit them and their mission. This was especially the case in energy management of their robotic labourers, Quarks. The Dominators used the Quarks for many tasks, but as they moved onwards and conquered other worlds, they found they needed the Quarks to use as foot soldiers, requiring slaves taken from their conquered worlds. (TV: The Dominators, PROSE: Mutually Assured Domination)
The Dominators were similar to humans in form, but over two and half metres tall with pale skin, dark hair and red-rimmed green eyes. (PROSE: The Dominators) Their ancestors were stocky, pale-skinned bipeds with dark hair, as vulnerable and naked as the humans of Earth. During the breakout from their home solar system, they experimented with physical augmentation. They made themselves taller, toughened their skin, and encased their bodies in armour plating. They moved slowly, but they were capable of running. They had eradicated sexual reproduction and instead became a mono-gendered species who reproduced by parthenogenesis. They altered their bodies to remove the need for food and obtained their energy from radiation, extending the normal Dominator lifespan by several hundreds of years. Their blood is purple. (PROSE: Mutually Assured Domination)
The Dominators used the Quarks as labourers in their forces. Though they used them for a variety of tasks, they preferred to use slaves where they could, in order to reserve their energy. Quarks were designed by Dominator Engineers to be easily transportable and adaptable: their cuboid bodies could be easily stored and transported, and the spherical, spired heads assembled from packs stored within a cavity inside the main casing. On low power, Quarks were able only to move very slowly, conserving their energies for their weaponry. A squad of high-powered Quarks, however, is a versatile and lethal tool, able to transform and expand into various configurations as the situation demanded it.
The Dominators used Neuro-Initiative Tests, or NIT. These tests were intelligence tests where the subject was shocked and then had to fit objects into similarly shaped holes. These tests were used to find out the suitability of other species for slavery and to determine their level of threat. At the same time, the Dominators conducted medical tests on those they captured, testing their intelligence level and their musculature to see if they were what they needed as slave labour. (PROSE: The Dominators)
The race that came to be known as the Dominators were once a human-basic tribe of hunter-gatherer-warriors dwelling on the planet Drahb in the Phi-Ralix galaxy, second to the Domina, the female rulers of the planet. Given too much autonomy and power, the males revolted and fled the planet. They quickly developed a highly industrialised technological society based on atomic power which fuelled their society. They experimented on themselves, becoming stronger and learnt how to reproduce artificially to become a mono-gendered race. They mastered space flight through the use of negative mass flux absorption – utilising radiation for power – and conquered first their home solar system, and then the entire Phi-Ralix galaxy.
They spread out and conquered the easily conquerable races like Bandrils, Tivolians, Gonds, Gurdels and Monoids, while at the same time calling themselves the Masters of the Ten Galaxies. However this claim was seemingly more propaganda than fact.
Their command structure expanded, with a clear chain of command from the lowest ranks (Probationers) up to the middle ranks (Navigators, Tacticians, Engineers) to the top ranks (Directors) and the Dominant Echelon of the War Fleet.
The need for power was their one constant problem. During their escape from the Phi-Ralix galaxy, they found their resources were spread thin. The Dominators cultivated a strict culture of power conservation. Waste of energy was considered a capital offence, and Probationers were rigorously trained in the techniques of power management. It wasn't uncommon for internal conflicts - weak leaders were replaced, but it wasn't impossible for mutinous subordinates to be executed. At the same time, all Dominators were meant to be disciplined and detached at all time. In addition, Dominators made use of enslavement of the conquered to help build their empire, and also constructed a tool to assist in their programme of expansion; a robotic slave force they called the Quarks.
Such measures allowed the Dominators to expand. However, they required new sources of power to expand their empire ever further. Negative mass flux absorption required nuclear energy – radiation found in space, e.g. solar radiation, was not sufficient – therefore task forces were created to find new methods of acquiring negative mass flux energy. (PROSE: Mutually Assured Domination)
Several planets were researched, such as Epsilon Zero Gamma and Dulkis. The scouts sent to Dulkis consisted of Toba and Rago. The plan was to take the strongest Dulcians as slaves and then use a special seeding device dropped into the magma of the planet in order to destroy it. This destroyed planet would then have its energy used for powering the Dominator fleet. Though the majority of the Dulcians were unwilling to fight back, some helped the Second Doctor stop them from destroying the planet. (TV: The Dominators)
The Dominators tried to invade Earth in the 1950s. Anyone who discovered their Quarks before they intended were stunned and held in confinement. The Dominators were defeated by the Tenth Doctor. (COMIC: Quiet on the Set)
A new attempt was made in 1969, this time using a cover identity of Dominex Industries. Director Vaar was the head of a special task force sent to the Milky Way galaxy for that very purpose. They bribed the UK government with the promise of cheap energy in order to get the nuclear waste they needed to wipe out the planet and use it for fuel. This plan was thwarted by the efforts of Alistair Gordon Lethbridge-Stewart and Harold Chorley. (PROSE: Mutually Assured Domination)
The Dominators launched an ultimately failed invasion of Gallifrey by flooding the Capitol with Quarks, 39 of which were destroyed by Leela and K9 Mark I. Though the Fifth Doctor would claim that there was never "any serious risk of us being conquered", one of the Quarks was fitted with a bomb which heavily damaged the Capitol, necessitating the construction of a replacement building. (AUDIO: Time in Office)
In the video game Happy Deathday, played by Izzy Sinclair on the Time-Space Visualiser, a Dominator was among a host of "every single enemy" that the Doctor had ever defeated, who were assembled by the Beige Guardian and pitted against the Doctor's first eight incarnations. (COMIC: Happy Deathday)