CyberMasters

"Time Lord organics with the ability to regenerate and self-repair in Cyber armour. Invincible! A perfect army, right?"

First Regular Appearance	Last Regular Appearance
The Timeless Children	The Power of the Doctor

A race of Cybermen built around the biology of Time Lords, capable of regeneration, capable of infinite conquest, capable of becoming an unstoppable force. To prevent this required the ultimate sacrifice from the Doctor, which the Master watched with glee: had he finally defeated his oldest enemy? The rage and insanity driving the Master found a new outlet on a destroyed Gallifrey when he used the bodies of Time Lords combined with the Cyberium to create a whole new race.