Skeletoid

The Skeletoids were a humanoid species who invented intelligent battle suits which could take over their wearers. They required a living human in order to function. These humans would be mind-controlled and preserved by the suit, though they would look like decayed corpses. (COMIC: Kane's Story)

History
During the 82nd century, the Skeletoids invaded the galaxy of Mutter's Spiral. Having invented the battle suit, the Skeletoids swept through five star systems in under a year. As they did so, the Skeletoids improved their battle suits, making them stronger, faster and fitting in more and more solid state circuitry, resulting in the suits becoming intelligent. As the battle suit units became more and more sophisticated, the wearers within became more passive until the human part of the Skeletoid was taken over by the machine.

Showing no mercy, the Skeletoids exterminated most of the species they conquered while fitting the biggest and the strongest with battle suits, effectively converting them into Skeletoids. The non-humanoid races in their path were slaughtered with casual efficiency as the Skeletoids emerged as a serious threat to even the Daleks and the Cybermen. Having demolished the two "mighty empires", the Skeletoids advanced on the Planetary Federation.

They finally came to the Draconian Empire and were destroyed by Abel Gantz. (COMIC: Kane's Story, Abel's Story, The Warrior's Story, Frobisher's Story)