Jegg-Sau

 was a planet. Robert Eliot Whitman stole plans for K1 and made it try to build a colony on this planet. (AUDIO: The Relics of Jegg-Sau)

Behind the scenes
Jegg-Sau was named as a homage to the Enemies of Doctor Who jigsaw puzzle, its image of multiple Giant Robots having been the inspiration for The Relics of Jegg-Sau. (DWM 412)