Heart of TARDIS (Dave Stone)

 Name: The Collectors

 Format: Book.

 Time of Origin: Unspecified, but they have expanded across a sizeable portion of the universe and exist into the far future.

 Appearances: "Heart of TARDIS" and "The Slow Empire"

 Doctor: Fourth Doctor and Eighth Doctor.

 Companions: 1st Romana, K9, Fitz Kreiner and Anji Kapoor

 History: While the Collectors are not explicitly evil, they have an obsessive fixation on collecting objects that belong to others that has made them a potential threat to other races in the universe, although The Doctor has never fought them directly.

  The main strength of the Collectors as an invading force is the completely illogical and haphazard nature of their ships' attempts to manoeuvre; any attempts to retaliate against the Collectors as they approached the planets they intended to 'conquer' fell apart when the planets' defensive networks suffered the artificial equivalent of a nervous breakdown trying to keep track of their ships' erratic movements, due to their use of the hyperwobble drive and psychonomic shielding (The Eighth Doctor once claimed that their ships are made from the ruined parts of other ships, but the Collector he was talking to denied this, and given his amnesic state at the time he may have simply made a mistake). On a biological note, Collectors are metamorphic, possessing a complex internal skeletal structure and various potential organs and appendages that can be grown on demand, although they can only manifest new body parts by conscious thought rather than automatic 'evolution'.

  Over time, the Collectors achieved such a significant reputation that even the Daleks apparently decided to resort to an elaborate deception to convince the Collectors that Skaro had been destroyed rather than fight them when they heard that the Collectors were in the area, with it being widely agreed that the only way to stop the Collectors attacking a planet is for the planet to get out of the way. However, the Collectors eventually realised that, having spent millennia collecting items, they were now left with a large collection of objects that they didn't actually know what to do with, prompting them to open a massive museum which they named the Big Huge and Educational Collection of Old Galactic Stuff (The Collectors clearly had little real talent for innovation in terms of names; one wing of the Big Huge and Educational Collection of Old Galactic Stuff was called the Hall of Big Pretend-Move Animals But Don't 'Cause They're Dead and Have Sand Stuck Up Them).

The Slow Empire (Dave Stone)

  The Fourth Doctor and Romana were forced to visit the Big Huge and Educational Collection of Old Galactic Stuff after they accidentally left K9 behind during a visit to Earth and determined that picking him back up when he was an exhibit there would be the best time to collect him without significantly impacting history ("Heart of TARDIS"). Although they were subsequently forced to flee the Collectors when The Doctor's plan to recover K9 simply consisted of breaking the case holding him, grabbing the robot dog, and running away, the Collectors were unable to catch the two Time Lords as their attempts to transform while pursuing them focused on appearing intimidating, the creatures taking too long to realise that they should redesign themselves for speed instead and thus giving the Time Lords time to reach the TARDIS.

  The Eighth Doctor encountered another Collector while exploring an area of space inhabited by the Slow Empire, a region of space where the laws of physics were so corrupted that time travel and faster-than-light travel were impossible (The TARDIS was able to travel between planets, but it took a few hours and was unable to travel in time in the process) ("The Slow Empire"). While visiting one planet, The Doctor encountered a Collector that had crashed on this world by accident, recognising it despite his currently-addled memory ("The Ancestor Cell"), the Collector deciding to accompany The Doctor so that he could take it back to its Collection.

  Despite its initially selfish motives, this Collector proved useful in helping The Doctor dismantle one of the damaged Pylons used for teleporting around the Empire - albeit by taking some of its parts so that it couldn't be reconstructed later -, later helping him rewire the TARDIS's secondary console to stop the alien race that had been using the Pylons to invade and control the Empire, simultaneously shutting down the Pylons. When The Doctor departed, the Collector remained behind with their current ally Jamon, a rogue and former miscreant who had provided them with useful local knowledge, to help him explain what had happened to the rest of the worlds in the Empire and rescue anyone trapped on random planets when the Pylons were destroyed while they were in transit.