The God Mars Book Four: Live Blades - The God Mars, #4

The God Mars is a pulp-style science fiction series set in a rich world of varied cultures and colorful characters. The series plays out a partially-terraformed Mars, a half-century after a man-made disaster cut thousands of colonists off from Earth, and the fear of a rampant nanotech plague prevented rescue. Left to survive for generations with few resources, the various groups develop unique new cultures at different levels of technology, ranging from the primitive to the frighteningly advanced.
But all are trapped in an escalating war between an oppressive Earth that's terrified of potentially infectious nanotechnology, and invincible superhumans-both heroes and villains-who claim to be from a nightmare future caused by that technology. In Book Four: Live Blades, Earthside Command's reckless use of a nuclear weapon has threatened the lives of those living in Melas Chasma, prompting a local band of Nomads to seek a new home in the more livable-and more dangerous-Coprates Chasma to the east.
Among their number, the adopted son of a Nomad Sharif hopes to find out who his birth parents were, as his people face strange and devastating new enemies. Meanwhile, a young Eternal embarks on a reckless journey to try to prove himself as a hero, a former enemy combatant tries to earn her place in the UN planetary forces, and a terrifying new threat arises from a world that never happened.