11 Best Sci-Fi Mercenary Books

I read John Scalzi’s Old Man’s War not long ago and I really loved the whole mercenaries and military aspect of the book. I immediately read all the sequels as well and the books are a solid read for sci-fi lovers.

But, even after reading all the books, I still had some cravings for similar books and started looking for some sci-fi books with mercenaries who are in it for the money or other selfish reasons.

Here is a list of all the great Sci-Fi Mercenary books I could find. Let’s start…

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1. Old Man’s War by John Scalzi

The first thing John did on his 75th birthday was to visit his wife’s grave and then he joined the army, but not just any army, he joined the space army fighting against the alien races for a claim on habitable planets.

The army only wants old people; people with experience and skills. Once he leaves, he can never come back and must serve for at least two years. If he survives the brutal war, he’ll get his own piece of land on one of the colonies of Earth. But first, he must be upgraded using Genetic Engineering.

2. The Forever War by Joe Haldeman

A war has been waged on a far-off planet between humans and an alien race called Taurans. Soldiers from Earth are sent to the battlefield using space travel which usually takes months travelling at the speed of light.

Private William Mandella is one of the many soldiers traveling through space to fight a war light years away. But, traveling at the speed of light has its consequences. While he only ages a couple of months, Earth has already aged years.

Soon, he finds himself rising through the ranks but becoming an outcast as he becomes one of the oldest humans alive. The home he knew and wanted to protect doesn’t exist anymore.

3. Consider Phlebas by Iain M. Banks

Horza, a shapeshifter, and his motley crew of mercenaries are hired by a three-legged race of aliens called The Idrians to help them in their war against another race called The Culture which used to be a peaceful community.

After a big fight, a powerful AI known as Minds, belonging to The Culture, escapes to a dangerous planet that no one dares to approach. Now, it is up to Horaz and his crew to retrieve the Minds before the Culture gets their hands on it again.

4. TheWarrior’s Apprentice by Lois McMaster Bujold

To follow in his warrior father’s footsteps, Miles enrolled in the Military Academy and aced the written exam but due to his weak body, he failed the physical exam and his career ended before it even started.

But, he’s not ready to give up just yet. Soon, he finds himself buying an old ship and starting his own mercenary crew. His first job is to obtain a cargo ship of dangerous weapons headed towards a warzone.

Will he make his father proud and make a name for himself as a mercenary commander?

5. The Space Between Worlds by Micaiah Johnson

People can now travel through the multiverse but no one is allowed to travel to a world where their counterpart is still alive to avoid any complications.

Fortunately for Cara, her counterparts are very good at dying. She travels through the multiverse, lives in a wealthy city, flirts with her handler, and soon will get her citizenship as well.

But, things take a bad turn when one of her only 8 remaining counterparts is killed mysteriously and she finds herself in a new world trying to solve the mystery behind her own death.

6. Fortune’s Pawn by Rachel Bach

Because of her love for combat and her powerful armor, Devi is one of the best mercenaries for hire. She plans to one day join the most elite unit on the planet, The Devastators.

Only the best can join the Devastators and she finally has a chance of making it when she gets hired as a security guard on the most dangerous trade ship ‘The Glorious Fool’. The owner of the ship has connections that can help her, as long as she can survive one year on the ship.

7. Dorsai! by Gordon R. Dickson

Dorsai! is the first book in the Childe Cycle Series spanning over 11 books that started back in 1959.

Dorsai are the most feared group of mercenaries throughout the galaxy because of their superior strength and fighting abilities.

Donal Graeme recently graduated from the academy and is one of the newer Dorsai in a long line. His talent even amazes his fellow warriors and he will go on to become the sole protector of the entire human race.

8. Falkenberg’s Legion by Jerry Pournelle

Earth is destined for destruction and no one can prevent it. Humanity’s last hope is the colonies in space with barely enough resources for survival.

People hope that one day someone with vision and strength will save the last remaining pieces of the human race and build a civilization spanning throughout the galaxy.

9. Shockwave by Lindsay Buroker

Casmir’s simple and perfect life is ruined when he’s attacked by robot assassins at the school he teaches.

With no idea of who’s after his life, he’s forced to escape from Earth altogether with the hopes of buying himself some time to figure things out.

But, trouble follows him in space as well as he finds himself entangled with space pirates, mercenaries, and all kinds of criminals, including the most notorious of them all – Captain Tenebris Rache.

10. Hammers’s Slammers by David Drake

Whenever a planet is faced with threats they can’t deal with like insurgents and terrorists they hire the most powerful and dangerous mercenary group in the galaxy – Hammer’s Slammers.

The members of Hammer’s Slammers are cold and ruthless, willing to kill anyone for the right price and sell their services to the highest bidders.

Follow them on their exploits from one world to another taking dangerous jobs.

11. The Forlorn Hope by David Drake

A band of mercenaries is hired by the government of a planet to fight against the religious extremists in a civil war. But, their side is losing and they’ve already lost many men.

To make matters worse, they get betrayed by the people who hired them and are to be sold to the enemies. Now, they must fight against the world with the remaining guns and tiny ships they have left and somehow escape the planet.

12. Volatile Rebirth by Jasper Hammonds

The war between the superheroes and the villains came to an abrupt end when all of them suddenly vanished and the normal people were left to deal with the destruction by themselves.

Logan Stone somehow makes end meets by working as a mercenary. While on a mission, he meets the most dangerous assassin on the planet, Card.

They begin a partnership and start taking contracts together, and after falling in love they plan to retire, but first, they must complete one last job by a powerful crime syndicate called The Family.

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