„As you know, I used the original meaning of the word Warlock, wǣrloga, which comes from Old English and means “oath-breaker”.
When the Witch of Endor calls Mars Ultor “Warlock”, she is, of course, referring to the last time he broke his oath and betrayed the humani. But […] Mars is NOT The Warlock of the title. The book is filled with oath-breakers, people changing sides, changing their minds. We have Billy and Machiavelli of course, but also Aten who may be betraying his world and Anubis who is betraying his brother. Then Josh betrays Sophie and of course Dee betrays everyone. And what about The Witch of Endor – what are her motives? […] The Warlock – the oath-breaker – of the title refers to a character who has made the biggest change, the biggest decision and acts out of character.
And that is… Niccolò Machiavelli.“
- Michael Scott