Doctor Who producer Phil Collinson addresses how editing decisions in the colorization of Patrick Troughton’s final Second Doctor story “The Wars Games” may have established a new incarnation of rival Time Lord The Master. Created by Terrence Dicks and Barry Letts for Jon Pertwee’s Third Doctor’s era, the rogue villain Time Lord was first portrayed by Anthony Delgado in 1971’s “Terror of The Autons”. Concluding Troughton’s Doctor Who tenure, 1969’s “The War Games” saw the TARDIS materialize on a mysterious world, where alien masterminds have abducted human soldiers from throughout human history to create a perfect army.

https://screenrant.com/doctor-who-the-master-retcon-war-games-producer-response/