Second paragraph of third section (“Rogues: The Battling Time Lords”, by Rob Levy):

While planning Season 8, producer Barry Letts and script editor Terrance Dicks decided to give Jon Pertwee’s third Doctor his own proper archenemy. Using the Sherlock Holmes/Professor Moriarty template as a guide, they birthed the Master, a mysterious antagonist that was the antithesis of the Doctor in almost every way.

Another of the unofficial Doctor Who annuals for the years when Old Who missed out, this time featuring the Sixth Doctor and (mostly) Peri and (sometimes) the Ainley!Master. Shorter than the Unofficial 1972 Annual. Two successive stories feature carnivorous plants, which is a bit of an editorial slip. The one I liked best was “A Weaponised Personality” by Christopher Swain-Tran. Out of print.