Klytode

The Klytode was an reoccurring enemy of the Doctor.

In 3769, the Doctor encountered the Kyltode on Space Station Alpha. (DWAM: The Snag Finder)

In 4014, the Doctor defeated the Klytode for a second time when he tried to destroy the Earth by releasing toxic bombs around the world's weather control centre using a delegation of androids. When the androids learn that they would be destoyed in this plan, they turned on the Klytode. The Klytode was captured and when he said he would never change his ways until the Earth is destroyed and the Doctor totally humiliated, he was left to be held under lock and key. (DWAM: Return of the Klytode)