Again, this is another difficult choice, because Diana Wynne Jones was excellent at providing realistic antagonists, whether human or otherworldly, ranging from malevolent goddess embodied in a doll, the Monigan, from Time of the Ghost, to the warlock Balsam brothers in Charmed Life, or nasty siblings Shine and Archer from Archer’s Goon, or the even nastier Mr Chesney from The Dark Lord of Derkholm, who doesn’t see Derk’s world as anything but a playground. The way that Jolyon’s presented in The Game reminds me a little of Mr Chesney, too, though his villainy is rather different.
Then there are the various earls in the Dalemark quartet, as well as evil mage, Kankredin, and the evil done inadvertently by characters who think they’re doing the right thing. Kathleen’s awful aunt Duffie in Dogsbody makes everyone in her house miserable, but she’s horrifyingly realistic. Sybil and Sir James in The Merlin Conspiracy have that satisfactory hamartia which makes their eventual downfall inevitable, but it’s the almost inexplicable hatred that Japheth and Joel have for Nick that’s scary and horrifying.
Or there’s the otherworldly Laurel from Fire and Hemlock, using up lives, and not caring who gets hurt in the process, and Mr O Brown from Enchanted Glass, who’s not quite the same person as in Midsummer Night’s Dream. There are various unpleasant witches, such as the Duchess in The Magicians of Caprona (whose ending always makes me think of Webster’s The White Devil) or Gammer Pinhoe losing her mind and persuading her family that murder is a good solution to their problems in The Pinhoe Egg (though Jed Farleigh is equally unpleasant).
I think, though, that the best villain is Orm Pender, Reigner One, from Hexwood. Not content with making sure he stays at the top of a galaxy-wide commercial enterprise – for centuries – by any means necessary; lying, cheating, betraying and murdering; he is a sadist who cultivates the appearance of a kindly old man, whose mental powers can compel almost anyone. It doesn’t help that he’s surrounded himself with less powerful but also unpleasant people. By the time he appears on Earth, the reader already realises that he is not a nice man, but it’s the revelation of how he has created the Reigners’ Servants which is particularly sickening, and particularly what he does to Kessalta. One feels like cheering at the way he’s finally out-manoeuvred.