ABC

A

Absorballoff
Home Planet: Clom
Life Form: Gelatinous
Info: The true species of this alien is unknown, its name was given to it to fit its nature - that of absorbing people for energy. It has the ability to disguise itself in human form, and move very quickly when needed.

Clom is a sister planet to Raxacoricofallapatorius (home of the Slitheen) so there is a suggestion that the Absorbaloff is related to them. During the events of Davros' return, Clom was stolen and hidden in the Medusa Cascade as part of a planetary machine.
Episode appeared: Love and Monsters


Adipose
Home Planet: Adipose3
Life Form: Fat
Info: Adipose are cute, really cute. Although their adult form is an unknown one.

It is later learned that if the Adipose had not left Earth, their creation would have wiped out millions of Americans. During the events of Davros' return, Adipose3 was stolen and hidden in the Medusa Cascade as part of a planetary machine.
Episodes appeared: Partners in Crime, The Stolen Earth

Atraxi
Home Planet: Unknown

Life Form: Partially crystalline

Info: The Atraxi were space police who wanted to catch Prisoner Zero.

Episodes appeared: The Eleventh Hour, The Pandorica Opens (briefly)

Autons
Home Planet: Unknown (possibly Polymos)
Life Form: Living Plastic
Info: The Autons themselves are merely shop-dummies, brought to life and controlled by the Nestenes. However, they have some added features such as a dun stored in their hands.

They appear somewhat brainless, used simply as slaves and killing machines. More sophisticated Autons can be created, which look and act human except for a slight sheen to the skin and a flat sounding voice
Episodes appeared: Spearhead from Space, Terror of the Autons, Rose, Love and Monsters


B


Baltazar
Home Planet: Unknown
Life Form: Unknown Humanoid
Info: Baltazar was a space pirate, referred to as "Scourge of the Galaxy", who had once been imprisoned on Volag-Noc. Initially he was determined to compress all of life on Earth into diamond, the Doctor and Martha stopped him.


Later on, Baltazar escaped from Volag-Noc and went on to search for the lost ship, the Infinite, via some data chip. He owned a pet metal bird called Caw who told the Doctor and Martha of his plans. But it was a trick as Baltazar figured he would let the Doctor find the Infinite for him.
Episode appeared: The Infinite Quest


The Beast
Home Planet: Unknown
Life Form: Deamon/humanoid
Info: The Beast was imprisoned before time by the Disciples of the Light in the bowls of the planet Krop Tor (The Bitter Pill) This planet was then suspended above a black hole to ensure that the Beast never escaped.


Although it looks demonic, it is capable of speaking intelligently and even displayed slight psychic tendencies as it hints at knowing peoples pasts and their futures. It is also able to transport its mind into others, and attempted to escape its prison via these means.

In a later episode, the Doctor states that the Beast was the devil, although at the time he refused to believe this, only acknowledging the Beast's existance rather than what it was.
Episodes appeared: The Impossible Planet, The Satan Pit


Blon Fel-Fotch Pasameer-Day Slitheen
Home Planet: Raxacoricofallapatorius
Life Form: Raxacoricofallapatorian
Info: Blon was a member of the nefarious Slitheen crime family. When on Earth she took the identity and appearance of Margaret Blaine, an MI5 official who was killed so that her skin could be used as a disguise. She and her family tried to push the Earth into a nuclear war, and use the remains of the planet for fuel.


Although she was apparently killed in an explosion, she teleported out at the last minute and become the lord mayor of Cardiff. However, this plan failed and she ended up looking into the "heart of the TARDIS". With this and the Doctor's encouragement, she regressed to an egg and was returned home so that she could start her life afresh.
Episodes appeared: Aliens of London, World War Three, Boom Town


C


Max Capricorn
Home Planet: Sto
Life Form: Stoan Cyborg
Info: Capricorn owned the spaceship Titanic. Although his head was still recognisably humanoid, the rest of his body was of cyborg design. He sabotaged the Titanic so he could get revenge on his company, using the Hosts as the tools of his destruction.


He planned to turn the Titanic into a giant bomb heading for Earth and use the resulting nuclear explosion to remove the board members of his company. However, his plan was foiled by Astrid Peth and both were subsequently killed.
Episodes appeared: Voyage of the Damned


Carrionites
Home Planet: Rexel 4
Life Form: Humanoid
Info: The Carrrionites first existed in the dark times, and were banished by the Eternals due to a war with a similar race, the Hervoken. They used words to channel energy in the same way we might use numbers and formulas to create extreme power.


The Carrionite's science largely resembles what we might call magic, using a crystal ball to spy on events, small puppets to control and kill people (similar to voodoo), and being able to find out a persons name and use it against them.
Episodes appeared: The Shakespeare Code


Lady Cassandra O'Brien.Δ17
Home Planet: Earth
Life Form: Modified Human
Info: Cassandra claimed that she was the "last pure human" left in the universe, and that her parents were the last to be buried in the Earth's soil. Although the race of humans spans out across the universe by this time, she refuses to acknowledge them, thinking they are "mongrels"


Despite the fact that she has had 708 operations, and has been reduced to a stretch of skin on a metal frame, she is incredibly vain, thinking that she is beautiful. Although she express the fact that she missed having a body when she transfers her consciousness into Rose.
Episodes appeared: End of the World, New Earth


Cat Race
Home Planet: New Earth
Life Form: Humanoid Feline
Info: The cats were the original inhabitance of the planet New Earth. By the time that people began colonizing the planet, they had evolved into humanoids, although they retained their feline faces and retractable claws.


When born, the cat people look just like regular felines but after ten months they loose their tails and begin to become more humanoid. They do however keep a somewhat haughty attitude towards other species. (see Sisters of Plenitude)
Episodes appeared: New Earth, Gridlock


Chantho
Home Planet: Melcarisso
Life Form: Humanoid bug
Info: Chantho's kind lived in a conglomeration in a network of caves and passageways just under the planet's surface. However, since then, the conglomeration has died and Chantho is the only one remaining.


For her species it is considered incredibly rude to not begin and end each sentence with the syllables of their name. So Chantho must begin each sentence with "chan" and end each one with "tho". It became obvious that she loved Professor Yana, but when he emerged as the Master, she was killed.
Episode appeared: Utpoia


Clockwork Droids
Home Planet: Earth
Life Form: Robotic
Info: The Clockwork droids were formally the repair droids of a 51st century ship. However, the ship crashed and the droids programming ordered them to repair with any means necessary, and that included using the crew.


Each droid is equipped with a short distance teleport, usually used to travel within the ship (or through the time holes opened within the ship) and a dangerous cutting weapon as part of their hands. Since they are clockwork, they will quickly wind down if they are away from the ship for to long. Episode appeared: The Girl in the Fireplace


Cybermen
(See here)


(Second part continued here: D-F)