Kamelion

Kamelion was a shape-changing android and companion of the Fifth Doctor.

Used by the Master to impersonate King John, he was later taken aboard the TARDIS by the Fifth Doctor. This continued until his destruction after he had again fallen under the influence of the Master.

However, this was not the end for him. He gained and lost a new host body, had a child with the Doctor's TARDIS and used his mental link with the Doctor to allow the Master to trap the Doctor within a dreamscape.

Kamelion was created from structure mathematics via Block Transfer Computations, (PROSE: The Crystal Bucephalus) a complex mass of artificial neurons, controlled by simple concentration and psychokinetics. As such, he was able to change his appearance and form at will. (TV: The King's Demons) He could even apply the same transformative energies to other individuals, as when appeared to turn people to stone in the guise of Medusa. (PROSE: Mark of the Medusa)

Not only could he masquerade as various humanoids, but Kamelion could actually change his mass via a pseudo-metabolic extension into the fifth dimension, where he stored or drew on mass to suit varied body forms. (PROSE: The Ultimate Treasure) At various points, he changed his hands into weapons, and took the forms of a Gubbage Cone with many tendrils and a fifty-foot tall version of his standard body. (PROSE: The Crystal Bucephalus) In spite of his capabilities, however, Kamelion was still susceptible to water damage. (AUDIO: Devil in the Mist)

According to one account, the Kamelions were created by the Gelsandorans (PROSE: The Ultimate Treasure) as weapons of war during their invasion of the planet Xeriphas before leaving. Not knowing why they left, Kamelion shut down his consciousness. (PROSE: The Crystal Bucephalus)

According to another account, the Kamelions were created by the Kamille as servants to experience physical interaction through following the loss of their physical form. They were also sent to other planets such as Xeriphas as ambassadors. (AUDIO: The Kamelion Empire)

When the Master became trapped on Xeriphas, (TV: Time-Flight) he discovered Kamelion had been left behind by previous invaders. He used the android to impersonate many beings across the cosmos, all the while causing Kamelion to develop a conscience. In his next encounter with the Fifth Doctor, he was using Kamelion to impersonate King John, in order to pervert history by preventing the signing of Magna Carta. (TV: The King's Demons)

The Doctor freed Kamelion from the Master's control and invited him to join the TARDIS crew, although Turlough and Tegan were uncomfortable with him. (TV: The King's Demons)

Although Kamelion was eager to explore his own free will, he soon realised that his pre-programmed loyalty was too powerful to ignore, resulting in him falling under the control of the criminal psychopath Maximillian Arrestis while the Doctor, Tegan and Turlough investigating strange goings on at a time-travelling restaurant in the far future. However, Kamelion was able to assist the Doctor despite being officially under Arrestis's control when he was ordered to turn into something dangerous to threaten Arrestis’s enemies; Kamelion obeyed the order by transforming into a Sculti - a race that generated a bio-electric field capable of shutting down the human brain - but neglected to inform Arrestis that the same field could also shut down the energy weapons that Arrestis was using. This allowed the Doctor to gain the upper hand in the subsequent confrontation and send Arrestis - who had been rescued from the moment of his own death - back to the point in time where he’d come from. Despite the fact that he had prevented any serious damage being done, this adventure prompted Kamelion to resolve to remain inside the TARDIS from then on, his use as a weapon by Arrestis to kill someone proving to himself that he couldn't be trusted. (PROSE: The Crystal Bucephalus)

Kamelion subsequently spent most of his time in his room in the TARDIS, consisting of a chair with a link to the TARDIS's databanks, allowing him to 'listen' to the ship reflect on its adventures. However, after meeting the Doctor's first three incarnations (TV: The Five Doctors), Tegan tried to use Kamelion to show Turlough what the Doctor had looked like when she first met him. Unfortunately, this resulted in Kamelion overloading as he tried to access Tegan and Turlough’s subjective experiences and impressions, prompting The Doctor to provide him with a casket to shield him from data he couldn’t process properly (PROSE: Qualia).