Kill-Mech
According to some variations of sources, Kill-Mechs were present on the planet Dispater in the 26th century, when they attempted an invasion. This was, evidently, at the exact same time as a Dalek invasion of the same planet. (COMIC: Star Tigers)
Behind the scenes
The Daleks were originally to have featured in part six of Star Tigers, when they would have been seen closing in on Dispater. However, the instalment had to be rewritten and revised to replace the Daleks with the Kill-Mechs, totally original creations, when it was rumoured that Terry Nation was planning to withdraw the licence to use the Daleks in the strip. Fortunately, it turned out Nation had no such intentions and the Daleks returned in part seven. The Abslom Daak: Dalek Killer graphic novel restores the original dialogue and art, removing the Kill-Mechs altogether.