Mary Gentle

This author also writes under the pseudonym of Roxanne Morgan

Excerpted from Wikipedia:

Mary Gentle's first published novel was Hawk in Silver (1977), a young-adult fantasy. She came to prominence with the Orthe duology, which consists of Golden Witchbreed (1983) and Ancient Light (1987).

The novels Rats and Gargoyles (1990), The Architecture of Desire (1991), and Left to His Own Devices (1994), together with several short stories, form a loosely linked series (collected in White Crow in 2003). As with Michael Moorcock's series about his anti-heroic Jerry Cornelius, Gentle's sequence retains some basic facts about her two protagonists Valentine (also known as the White Crow) and Casaubon while changing much else about them, including what world they inhabit. Several take place in an alternate-history version of 17th century and later England, where a form of Renaissance Hermetic magic has taken over the role of science. Another, Left To His Own Devices, takes place in a cyberpunk-tinged version of our own near future. The sequence is informed by historically existing ideas about esotericism and alchemy and is rife with obscure allusions to real history and literature.

Grunts! (1992) is a grand guignol parody of mass-market high fantasy novels, with orcs as heroes, murderous halflings, and racist elves.