Set in a dark future devastated by climate change, Tool of War is the third book in a major adventure series by an award-winning science fiction author, featuring the most provocative character from the acclaimed novels Ship Breaker and The Nowned Cities. In this striking and eerily prescient science fiction thriller that Kirkus described as "masterful," a tool – a half-man/half-beast designed for combat – proves capable of far more than its creators ever imagined. He becomes a rogue of his pack of ingenious bioengineered "augmentations" and rises to become the victorious leader of a pack of human boy soldiers. But he is relentlessly hunted by someone determined to destroy him, who knows a disturbing secret: Tool has found a way to resist his genetically rooted impulses of submission and loyalty to his masters. The time has come for Tool to launch a full-scale war against those who enslaved him. From one from undisputed masters of science fiction comes a compelling and timely page-turner that explores the complex relationships between hunter and prey, master and slavery, human and monster.