Klytode android

The Klytode Androids were first seen guarding and protecting the Klytode hiding aboard Space Station Alpha in the year 3769. The Klytode planned to use a cobalt bomb to cause the space station to crash into Earth and change its climate. (DWA: The Snag Finders)

The Klytode Androids were also used by the Klytode (albeit with a different appearance) to destroy the Earth by exploding them at weather control stations around the world. Their destruction would have led to the release of toxin bombs destroying the planet. When the Tenth Doctor pointed this out, the Androids rebelled, not wanting to die. They turned on the Klytode and helped secure his capture and restraint on Earth. (DWA: Return of the Klytode)