House (The Doctor's Wife)

House was a malevolent entity which fed on TARDISes in a bubble universe for their Artron energy. It had servants it kept around for entertainment. House met its end when it tried to take over the Doctor's TARDIS, but was expelled by its Matrix.

Biology
House was a malevolent, mysterious entity which lived in a small bubble universe outside the main universe. House existed as an intelligence in a time rift. Its body was an asteroid-sized celestial object. At the time of his encounter with the Doctor, he implied that he was at least half a million years old.

The creature gorged itself on artron energy and at some point discovered the existence of the Time Lords, whose TARDISes were filled with just such a power source. It began using Gallifreyan distress signals to lure Time Lords to its surface, where they would be trapped. House would remove the TARDIS' matrix and devour the TARDIS. The trapped Time Lords would perish. House's encounters with the Time Lords led it to calling them a kind race.

The Doctor describes House as "a sort of sea urchin", with a tough outer shell protecting a soft interior. This idea was raised when Uncle introduced the Doctor to House through a mesh-covered hole, most likely a pore in the surface of the creature to the body at the centre. House was never shown to have any physical features, such as eyes or a mouth. except its shell. He could possess other lifeforms. He used Auntie and Uncle to speak when he first met the Doctor, Rory and Amy. The green glow in the eyes of Ood Nephew was presumably also an indicator of Houses' direct telepathic influence. (DW: The Doctor's Wife)

History
Uncle, Auntie, the Ood Nephew and Idris came upon House and lived on its surface. As Time Lords died there, he renewed the bodies of his servants and replaced parts of their dying bodies with dead Gallifreyans who had also stumbled upon House. They became an extension of his will and carried out his every wish. After the near-annihilation of the Time Lords in the Last Great Time War, House grew hungry and attracted the attention of the Eleventh Doctor, who was accompanied by Amy Pond and Rory Williams, by sending a psychic distress signal box, originally broadcast by a Time Lord called the Corsair, into their universe through the rift.

House used his powers to remove the Doctor's TARDIS' matrix and put it into the body of Idris, leaving it blank for it to be consumed. However, during a conversation with the Doctor, House learnt the Time Lords had perished in a terrible conflict. Realising its food source had been eliminated, House decided to change its behaviour by possessing the now empty TARDIS and using it to reach the main universe to find new sources of energy. The Doctor found the cache of hypercubes sent by the dead Time Lords House had trapped. The Doctor and Idris built a TARDIS from the scraps of old TARDISes about the asteroid to pursue House.

To amuse itself, House used the TARDIS to play with the minds of Amy and Rory. However, the Doctor caught up with House. The TARDIS matrix was released from her dying human body, allowing her to repossess the time ship. House's essence was expunged from the ship. (DW: The Doctor's Wife)

Behind the scenes
Writer Neil Gaiman said in an interview in Doctor Who Magazine #448 that earlier drafts of The Doctor's Wife implied that House was actually the Great Intelligence.