House
House was the name given to the asteroid in The Doctor’s Wife (Series 6 : Episode 4) by Auntie, Uncle and Nephew. House was a malevolent entity that existed in a ‘bubble universe’ just outside of our universe. House fed on Artron energy found in TARDISes and drew Time Lords to him to feed on. House’s body was the asteroid on which Auntie, Uncle and Nephew were his slaves. House used Time Lord distress signals (the hypercubes) to trick Time Lords into landing on him. When they did, he would drain the TARDIS matrix and feed on the Artron energy within. The Time Lords, stranded, were left to perish on House. If one of his slaves (Auntie, Uncle, Nephew or Niece (Idris)) were dying, House would use the bodies of the Time Lords to repair and heal them.
House removed the matrix of the Doctor’s TARDIS and placed it within Idris to regenerate her, but this caused Idris to become a human manifestation of the TARDIS itself. When House meets the Doctor and learns that the Time Lords have died out in the Time War, House changes his objective from feeding on the TARDIS to hijacking it and using it to enter our universe to find a new source of food. House was able to play about with the TARDIS while Amy and Rory ran for their lives for his amusement. However, the Doctor managed to find a way back onto his TARDIS, along with Idris. When Idris died, the TARDIS matrix returned to the TARDIS and expunged House’s essence from it, defeating House.