Nominated for both the Hugo Award for Best Novel and the Nebula Award for Best Novel, Ninefox Gambit is an English language science fiction novel publshed in June 2016 by American author Yoon Ha Lee. It is the first novel in the Machineries of Empire trilogy, and is followed by The Raven Stratagem, then by Revenant Gun.

Ninefox Gambit tells the stories of Kel Cheris, a mathematical prodigy in the military faction of a galactic empire known as the Hexarchate, and Shuos Jedao, an undefeated military general from hundreds of years past, whose "ghost" has been implanted in Cheris' mind, in order to utilise his skill to win a war against an invading alien force. This intention is significantly complicated by the fact that Jedao is insane, and Cheris has a number of convincing personal reasons - the genocide of her culture among them - to want to see the Hexarchate fall.

This novel is fast-paced, highly cerebral, emotionally intense, and explores themes of imperial colonialism, slavery, and the ethics of sacrificing the "few" for the sake of the "many," when those few being sacrificed did not volunteer for it and were already facing marginalisation by a fascist majority.

The Hexarchate presents an interesting model of society, in which the population are divided among six factions which specialise their skills for combat, science, espionage, and other areas, in the service of the empire. The author's educational background is on full display in this novel and the rest of the series; he attended Cornell University, majoring in mathematics, and he earned a master's degree in secondary mathematics education at Stanford University. The military employs "calendrical weapons," technology which operates according to a complex intersection of mathematics, physics, and what might be interpreted as magic, and which falters in the presence of mathematical operations in a different numeric base and calendar. Lee states in this interview by Seregil of Risingshadow,

For this novel, I considered coming up with a bunch of congruences and whatnot out of abstract algebra, and then my husband pointed out that nobody picks up a space opera novel because they want to read about abstract algebra. There are references to bits and bobs of math, like matrix diagonalization and fractals, but the main idea is that the magic system is basically math that affects reality, especially number theory.

The prose of all Lee's works tends to be elegant, even ornamental, and Lee cites Roger Zelazny as his primary influence in this regard, stating that Zelazny "was one of the authors who showed me that prose could be beautiful for its own sake." Ninefox Gambit is no exception, and it will definitely be enjoyed by those who love Zelazny's works, as well as anyone who read and enjoyed Lee's short story anthology, Conservation of Shadows. I can also recommend this book to anyone who enjoys the works of Ann Leckie, such as Ancillary Justice, and recommend the latter book to anyone who enjoyed Ninefox Gambit, due to the related themes and the military point of view of the protagonists of both works.

Iron Noder 2020, 25/30