Exxilon (species)

The Exxilons were an ancient humanoid species. Once a very technologically advanced culture, they mastered space travel and visited many planets while they were still primitive worlds, long before their respective native species reached the Exxilons' level of development.

However, the Exxilons outdid themselves with their own technological works, eventually building a monument beyond even their control. Their folly ushered in the destruction of their civilisation when it began killing them off in droves, causing them to greatly dwindle in numbers. The end consequence was their degeneration into a primal tribe society, after they surrendered to their own creation in fear and chose to worship it as a sort of god.

Biology
Following their descent to savagery, the Exxilons developed into two distinct sub-groups. They both had bark-like skin, inset eyes, flattened noses and wide mouths. They were both nocturnal and had large eyes adapted to the dark. One group of Exxilons were tall and powerfully built and lived on the surface of Exxilon. The other group were smaller, paler and lived deeper underground, with fluorescent markings on their bodies. (PROSE: Death to the Daleks)

Culture
The surface Exxilons had fallen further in development than the subterranean Exxilons and had little in the way of culture. They banned the use of advanced technology and any form of progress. They lived near the Great City, protecting it from intruders. They lived in the catacombs underground and would come out during the night. They were led by a high priest, who was the most sacred member of the tribes. The Exxilons would make sacrifices to the City, drugging prisoners and preparing them to be sacrificed in special temples deep underground. These rituals were long and complicated and if they were interrupted, they needed to be restarted.

The Subterranean Exxilons lived deep underground, trying to stay out of the way of the surface Exxilons. They retained much of the knowledge of the ancient Exxilons and feared the City, but only as a danger instead of a god. They wanted to destroy it for the good of the Exxilon race. (TV: Death to the Daleks, PROSE: Death to the Daleks)



Technology
The pinnacle of Exxilon technology was their Great City, which combined all their technology and outlasted their civilisation. (PROSE: Death to the Daleks)

Exxilon fuel pods were opaque spheres with plutonium inside for fuel. Even if the outside was damaged, it used a force field to protect against radiation.

A specific type of Exxilon technology was the Xiuhcoatl. (PROSE: The Left-Handed Hummingbird)

History
The Exxilons were an ancient species, apparently capable of space travel before life had formed on other worlds. They travelled throughout the Mutter's Spiral and were reportedly the most powerful species in the universe, at least for a short time. (TV: Death to the Daleks, PROSE: Death to the Daleks) The Tenth Doctor once recalled that in his youth, he had read of their species as one of the "Old Ones", species which had risen to prominence in the Dark Times only to fall from grace somewhat in later epochs. (PROSE: The Knight, The Fool and The Dead) At the height of their power, they influenced the development of other early civilisations, including the Earth. (TV: Death to the Daleks, PROSE: Death to the Daleks)

They were one of the species involved in the Millennium War, joining forces with the Uxarieans to fight the minions of the Mad Mind of Bophemeral in the Andromeda Galaxy. They were both caught in a trap that led to their eventual downfall and the creation of the Crab Nebula. (PROSE: The Quantum Archangel)

The Exxilons came to Earth during the early development of the Incan civilisation. They left their influences in their designs and did some unknown experiments on them. At the same time, they accidentally left behind the Xiuhcoatl and a ruptured fuel pod. Both of these were picked up by early Aztecs, and both had an influence on their civilisation. The fuel pod gave off radiation, causing mutations in the population and leading to the development of Huitzilin's powers. The Xiuhcoatl was also used by Huitzilin as a weapon of fear and terror, allowing him to control his citizens. (PROSE: The Left-Handed Hummingbird)

At some point, they also visited the planet Yemaya 4. (PROSE: Sleepy)

Eventually, the Exxilons decided to pool their knowledge and create the Great City of the Exxilons. It combined all of the science known to the Exxilons and was intelligent and capable of repairing itself. During this time, the Exxilons would travel to other inhabited worlds where they would construct great beacons on their surface that would drain the mental energy of the natives and send it back to the Great City. (AUDIO: The Exxilons) Eventually, the City decided that the only flaw left was the Exxilons themselves and it drove them out. The City drained all the energy from the planet, which meant the Exxilons were incapable of developing any technology above the stone age. They slowly descended into a primitive species. (TV: Death to the Daleks)

During the space plague at the end of the Third Dalek War, (PROSE: The Secret Lives of Monsters) humans came to Exxilon in search of parrinium. Their ship failed as soon as they reached the planet, and they were attacked by the primitive Exxilons as soon as they arrived. They tried to survive on the planet, but the Exxilons were a permanent danger. Shortly afterwards, the Third Doctor and Sarah Jane Smith came to the planet by accident, and Sarah was kidnapped to be sacrificed. Before the Doctor could do anything about it, the Daleks came to the planet, looking for parrinium which they could use to threaten the Earth colonies. They too were de-powered by the City, but after several defeats, they were able to modify their weapons, allowing them to fight back. They enslaved the surface Exxilons and forced them to mine the parrinium. While escaping from the Daleks, the Doctor and Sarah Jane encountered the underground Exxilons. The Doctor helped one, named Bellal, find a way into the City and destroyed it from within. (TV: Death to the Daleks)

When a second wave of the space plague struck the galaxy, the humans returned to Exxilon to mine parrinium, trading societal infrastructure for mining rights. The Exxilon Gislen distrusted the humans and their technology, making a deal with the Dalek Empire to install a new power-draining beacon. When the Fourth Doctor arrived on Exxilon, he and Leela exposed Gislen's duplicity to the rest of the Exxilons before the Marine Space Corps destroyed the beacon and the humans left the planet, taking the Doctor and Leela with them. (AUDIO: The Dalek Protocol)

During the Last Great Time War, the Time Lords, recalling the Great City's effect on the Daleks, dispatched time agents in an attempt to contact the Exxilon race at the earlier, more advanced period of their timeline, in the hope that they could provide technical assistance in the construction of a similar power-draining device. (PROSE: Dalek Combat Training Manual)