Trod 57

Trod 57 was one of the Trods who were constructed in 2066 on the planet Trodos by MacTaggart to give himself power over the other colonists, secretly using them to enslave everyone. When the First Doctor, John and Gillian arrived on the planet, they were captured by the Trods, but escaped and deactivated them. (COMIC: The Trodos Tyranny)

Later, the humanoid Master of the Trods reactivated the Trod 57 and its fellows to enact revenge on the Doctor. However, after their Master fell to his death, Trod 57 and the other Trods were commanded to destroy themselves by the Doctor, who fooled them into he was the Master of the Trods. (COMIC: Return of the Trods)