Hornet
This clearly needs a dab term, such as Hornet (The Stuff of Nightmares)
Talk about it here.
The Hornets were an insect species which resembled the hornets of Earth, capable of possessing lifeforms. They lived in the depths of space, but came to Earth by accident where they had multiple encounters with the Fourth Doctor. (AUDIO: Hornets' Nest)
Abilities
The Hornets were able to possess living beings, taking control of their mind. The Doctor described them moving from a body as a black smoke. From within a body they could verbally communicate, even that of an animal usually unable to speak such as a dog. (AUDIO: The Circus of Doom, A Sting in the Tale) The Hornets could also re-animate preserved bodies of dead creatures. (AUDIO: The Stuff of Nightmares) The Hornets were also able to influence people by stinging them. (AUDIO: The Dead Shoes)
The Hornets could also alter the size of matter at will, including their own bodies. (AUDIO: The Dead Shoes)
The Hornets were a hive-mind, though the swarm was led by a Queen who the rest served. (AUDIO: A Sting in the Tale)
History
Missing info from Hive of Horror and Sepulchre.
The Hornets were "blown" to Earth in 1039, struggling to survive they took possession of a pack of wild dogs and a pig near Tilling Abbey. Nuns belonging to the Abbey captured the pig, which contained the swarm's Queen, so the rest of the swarm used the dogs to lay siege to the Abbey. During this the Hornets encountered the Fourth Doctor for thr first time, although for the Doctor this was his fourth encounter with them as he had encountered the Hornets in reverse order. Reaching the pig, the swarm reunited in a single dog. The Doctor lured them to his TARDIS, taking them away from Earth. They took possession of him and forced him to take them back, arriving in Venice in 1768. As he refused to leave the ship. they left the Doctor and outside possessed Antonio. (AUDIO: A Sting in the Tale)
The Hornets used Antonio to set up the Circus of Delights. With Antonio as the ringleader, and the Hornets travelled from town to town, enlisting people to join the circus where they could influence them. They encountered the Doctor again in Blandford in 1812 where he mesmerised Antonio for information. In response the Hornets abandoned Antonio, leaving him dead, and took full possession of tightrope walker Francesca. As the Doctor closed in they compelled her to jump off the high wire to her death. The Hornets remained dormant in Francesca's dead body, and eventually, her mummified feet and ballet shoes would make their way to a museum in Cromer. (AUDIO: The Circus of Doom)
By stinging famous dancer Ernestina Stott, the Hornets were able to possess her and used Mrs Wibbsey's voice to command her to sacrifice her life to the sea. They possessed a China Doll in order to speak with the Doctor while he was inside the Victorian house. (AUDIO: The Dead Shoes)
They possessed stuffed animals and Ernestina's grandson Percy Noggins, the director of a factory. They thought the Doctor would be a good host, but he avoided this by escorting them to his home at Nest Cottage. (AUDIO: The Stuff of Nightmares)
