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To Tread Obsidian Shores

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WHAT DOES IT MEAN TO BE A WARRIOR?

The Protectorate of Mars Foreign A path to citizenship. A fresh start. Defending the Protectorate of Mars against all enemies, foreign and domestic.

HOPE

With itchy feet and a vagabond soul, all Blue ever wanted was to join the Survey Corps and explore the universe. But when she failed the entry exam, becoming a dropship pilot for the Legion was her last chance at achieving that dream. It was only supposed to be a stepping stone . . .

DUTY

All he ever wanted was a home. But when Tavi is driven from his world by murderous revolutionaries, he only has one chance to the Legion. Searching for a new life, he soon discovers something even better—a family.

WELCOME TO THE LEGION

At the publisher's request, this title is sold without DRM (Digital Rights Management).

Jason Cordova is both a John W. Campbell Award and Dragon Award finalist. He edited his first anthology, Chicks in Tank Tops, coauthored Monster Hunter Fever with Larry Correia, and wrote Mountain of Fire in the Black Tide Rising universe, all with Baen Books. He has 28 novels currently in print and has been featured in numerous anthologies. A Navy veteran, he is also a former middle school teacher. Though Californian by birth, he has since relocated to the South, where he swears at the humidity on a thrice-daily basis. He can be found at www.jasoncordova.com.

Melissa Olthoff. is a science fiction and fantasy author who delights in sneaking in romance wherever she can. She is a lifelong geek and a veteran of the United States Air Force, both of which are incredibly useful when writing. Her degrees in meteorology and accounting are slightly less applicable to writing but absolutely useful when it comes to supporting her family. In 2023, she took second place in the annual Baen Fantasy Adventure Award Contest with her story “Fall from Grace” and won the Imadjinn Award Best Short Story in 2023 and 2024. She is published by Baen, Chris Kennedy Publishing, Hit World Press, and Three Ravens Publishing, and is best known for her novel of the Griffin Corps, Rise from Ruin, and novels in the Four Horsemen Universe, the Blood & Armor Series, the Salvage Title Universe, and Hit World Valkyries, as well as numerous short stories.

Praise for Melissa

“. . . Olthoff creates not only a believable and immersive world, but populates it with people whom you can respect, understand, care for, and sometimes want to punch in the face . . .” —Jody Lynn Nye, New York Times best-selling author

Praise for Jason

“A great combination of story-telling skill and imagination that really hooks you.” —Larry Correia, New York Time best-selling author of Monster Hunters International

400 pages, Hardcover

Published January 6, 2026

2 people are currently reading
45 people want to read

About the author

Jason Córdova

76 books56 followers
Bestselling author Jason Cordova is both a John W. Campbell Award and Dragon Award finalist (though not in the same year). He is the author of Mountain of Fire and Monster Hunter Memoirs: Fever (w/ Larry Correia), and editor of Chicks in Tank Tops and Dancing with Destruction.

Along the way, he has had novels published in multiple languages around the world, been featured in over 40 anthologies, and has penned over two dozen novels across many genres, including YA, horror, science fiction, and urban fantasy.

A history nerd, he is a Navy veteran, former teacher, and is currently an Associate Editor at Baen Books.

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Displaying 1 - 11 of 11 reviews
Profile Image for Jonathan Koan.
886 reviews881 followers
January 10, 2026
Jason Cordova and Melissa Olthoff have turned in quite the entertaining military sci-fi story. We follow two different characters here: Tavi who is a young, new soldier in the Bronze Legion and Blue who is a pilot in the Bronze Legion.

I really loved Tavi's story. He is such an earnest and kind character who is trying to do the right thing and his unfamiliarity with the customs of the other soldiers in the Bronze Legion just made him delightful. There is a "bar fight" sequence that instantly sealed him as a top-tier character for me. He also has a potential slow-burn dynamic with a scientist named Mitzi that I thought was charming.

I also really enjoyed Blue's storyline, which felt very different from Tavi's. Blue is a bit more experienced, and while Tavi comes from the dregs of his society, Blue is from a more upper-class portion of her society, and seeing that being used both for and against her was fascinating. She also has a really sweet romantic subplot with the character Campbell that was really uniquely written, which made it even more fun to read.

The first half of the book was my personal favorite, as I loved seeing these characters connect and interact with each other. Around the midway point, a major event happens that changes the direction of the book. The plot didn't quite work for me for about 100 pages in the middle, but I was still incredibly invested in the characters. And then the plot absolutely picks up near the end.

There are a ton of references and inspirations from the French foreign legion, which I quite enjoyed. There are also many tuckerizations that were fun to realize.

Overall, I really enjoyed this book. Jason and Melissa just have a writing style that works for me and a set of character relationships that is really engaging. I'll give To Tread Obsidian Shores a 9 out of 10.
11 reviews1 follower
January 7, 2026
All of the Action.

This novel has elements of Blackhawk Down, 300, Starship Troopers (film and book), and hints of Aliens. Fast paced and is difficult to put down. Finished it in 24 hours. Ya, the authors nailed.
Profile Image for The One True Rob.
52 reviews2 followers
Review of advance copy
January 7, 2026
Hidden in this book, using the ancient Sumerian technique of ASCII supersanskript, with a SUM1024 reversible hash, Melissa and Jason have hidden the manuscripts for the other 17 books they have already planned and written for this series.  The data to reconstruct the private key, needed to reverse the hash is stored throughout the book.   I've given you the only clue needed unlock the "Advanced  Cryptologists eArc Version" of the additional Bronze Legion novels, all you have to do is decipher it and claim your reward.


Now, let's dive into this first book and dissect why it is so unbelievably awesome in a way that makes the word "epic" seem equal parts trite and trivial.  


First, let's examine the writing style of Melissa "Freaking Amazing 'Scrumptious' Taco Vendor Supreme" Olthoff (Don't ask me why someone, whose last name rhymes with Schmulff, nicknamed her "Scrumptious".  I'm just relaying the facts here. If you figure out who I'm talking about you can ask them.  I'm pretty certain nobody will decipher my impenetrable code though.  The rest of her nickname was earned by being freaking awesome and making supreme tacos, then selling them.)  Moving on, in my examination of her writing style I discovered she has the exact same style as Ruothild (daughter of Charlemagne), who was an Abbess of Faremoutiers in the 9th century.  There are only two things that could possibly explain this.  Melissa is either the reincarnated abbess, or she is the abbess, who faked her own death and slept in a hibernation pod until the world was ready for her books.  I have yet to unearth evidence to determine which is the truth, so I'll leave you to decide that for yourself.


Why this matters is that her writing is a gateway to another millennium and in the unlikely event that you do not already own all of her books, you should probably go out and buy them, so you can study her words and learn from the great wisdom she has to impart to us.  I've heard that she offers private wisdom bestowal sessions to those who show the proper reverence and respect, for a reasonable fee. (Don't quote me, but I believe she defines reasonable as "anything greater than the annual budget of Rhode Island".)


Next, let's move on to Jason "I Am Unaware of Any Nickname" Cordova.  Jason and I met briefly in Tucson in 1873, where he "won" my horse in a hand of poker.  I remain adamant that he must've cheated, but with no empirical evidence to back my theory I was forced surrender Nahar, who was gifted to me by Oromë, for cybersecurity services rendered.  This might have made a lesser man bitter and disinclined to like Mr. Cordova and possibly taint any analysis of his handwriting they performed.  Fortunately, that was never really a concern, because the book reviewers guild puts their members through rigorous training to ensure that we can remain completely objective at all times.


Now that we've established that my objectivity could not possibly have been compromised, I will share the stunning results my analysis uncovered.  Jason shares the exact same writing style of the head metallurgist for King Meskalamdug, in the First Dynasty of Ur.  Unfortunately, their name has been lost to history, but there is no doubt in my mind that Jason inherited his writing style from this Sumerian metallurgist, which makes the title "The Bronze Legion" make so much sense.


When we combine the two writing lineages, what we are left with can only be described as the greatest example of splenidifantastimarveloincrediglorispectaculositude writing the world has ever seen.  Some of you might be saying "that word is made up", but all words are made up, so your point is pointless and you would only receive a dismissive steely-eyed stare, in response to your statement.  


You may follow up with "If you just created the word, isn't the available sample size too small to declare something the greatest", to which I would reply "Poppycock and Balderdash, my good sir." (or madam)  


Then you would swoop in for the kill with "If it's the only example, wouldn't it also be the worst?", you would declare, your eyes alight with triumph, wearing a cocky smirk, and wrapped in the warm smugness of your certitude.  It would be in that moment that I would disembowel you with my reply: "The day may come when the splenidifantastimarveloincrediglorispectaculositude of this book fails, when we forsake all books we have reviewed and break all bonds of trust between author and reviewer, but it is not this day"


Crushed and weeping in shame, you would crawl away, utterly defeated by my unassailable logic and possessed with the sure knowledge that the only way to right the horrific wrong you attempted is to immediately buy this book and pour through its contents, consuming them as if they were the very elixir of life itself.  Only then would your guilt and horror be assuaged and your thirst for forgiveness be slaked.


Alternatively, you could just accept my declaration as gospel and just buy this book and enjoy it without all the self recrimination.  I know which one I already chose.
Profile Image for Brian Korslin.
2 reviews1 follower
January 12, 2026
The Bronze Legion

A rip-roaring great story! Well written characters that would fit into any mil-sci fi setting. I can not wait for the sequel!
Profile Image for Elizabeth Lobdell.
70 reviews
Read
January 8, 2026
To Tread Obsidian Shores Loved this book!
Devoured it in 2 evenings. If it had been a weekend I would have stayed up all night to finish it. Poor kid on the lam joins the Legion, rich gal with political ties flys the drop ship. No they don't hook up, but there is a touch of romance going on. Then there are the alien critters that are too smart on a planet. Explosions of all types!
Profile Image for Sharlyn Cox.
9 reviews
January 16, 2026
I've been reading books by Jason Cordova and Melissa Olthoff for the last few years, and have thoroughly enjoyed their work. But the two of them writing together? Chef's kiss!

From endearing characters, to page-turning action, to a gripping plot, and a burgeoning romance that feels true to life, this is one of the BEST books I've read in a long time.

Also, the bar fight scene was epic!!!

If you're looking for a new Sci-Fi series to dive into, grab To Tread Obsidian Shores. Fair warning: once you start reading, you will NOT want to put it down.

I can't wait for Book 2!
Profile Image for Howard.
429 reviews16 followers
November 13, 2025
I’d like to thank Baen books for an eARC of The Bronze Legion: To Tread Obsidian Shores by Jason Cordova and Melissa Olthoff with an expected publication date of January 6, 2026 in return for an honest review. I have read short stories and novels by both of these authors and was excited to see a new military sci fi series by the two.

The story revolves around two main characters: Blue, a drop ship pilot for the Legion and Tavi, a new member of the Legion. The Protectorate of Mars Foreign Legion, defending against all enemies, domestic or foreign is a marine like military group. Blue, from a politically connected family [her grandmother was a legend in the Survey Corps], is hoping that the Legion will only be a way station and that after three years she will be able to join the Survey Corps. Tavi is the bastard son of an elite class, that was overthrown and is hunted to be torn to bits as the book opens. Escaping into a Legion enlistment center provides him with a welcome rescue. His ability to survive in the alleys of his home-world provides Tavi with the background to excel in Legion training and is surprisingly placed with the toughest Legion company.

Additional players include a Survey Corps team tasked with determining if the planet Aurora is advanced and safe enough to be brought into the Protectorate. The team is led by an egotistical Expediter, Schmoyer, and includes child prodigy Dr Wingo. The research outpost on Aurora is led by Planetary Supervisor Norwood, from a politically connected family who will do almost anything to ensure that he becomes Governor of Aurora. The Navy is also represented, as the spaceship operators that deliver the Legion to their various assignments. This story has a lot of moving pieces and includes just over 50 characters in the Dramatis Personae at the start of the book.

Cordova and Olthoff do a masterful job of interweaving the number of characters and story lines (interpersonal, political, and strategic) in a clear and exciting manner. I connected with Tavi (and wished at times he got a little more page time) but this is a series, and I look forward to how he is handled in future books. Both authors are military veterans, and To Tread Obsidian Shores does an excellent job of portraying military action, but even more so, the day to day interaction of soldiers in military units. We have seen this before from Olthoff in her Rise from Ruin book; we also get a dose of romance, similar to previous books of hers. While personally, I am not always a fan of romance, it seemed true to life as to what would go on in a military unit and I appreciated it for that.

What seemed like a simple [if annoying] job of escorting a group of scientists from one remote research site to another, turns unexpectedly into a hair-raising battle of the elements and native wildlife. The battle scenes, and they are battle scenes, are extremely well written, and are engrossing, even if the battle is not against another military force. I expect nothing less from either author. The book as a whole is extremely readable, and you will be hard pressed to put it down. While the debut of a new series, To Tread Obsidian Shores comes to a satisfactory ending while leaving this reader curious where the various story arcs will go.

Highly recommended and rated at 5 stars.
2,726 reviews12 followers
January 18, 2026
Excellent military sci-fi!

Tavi joined the Legion to escape his poisonous home world and the murderous mob chasing him. The Legion gives him what he has never had – purpose, citizenship, and family.

Blue wanted to follow her grandmother’s footsteps in the Survey Corps. She failed the entry exam, but becoming a drop pilot for the Legion for a few years offers another avenue.

Outstanding! This is a page-turning, action-filled sci-fi adventure. I received an advance copy, but my review is honest and voluntary.
Profile Image for Sean.
112 reviews3 followers
January 7, 2026
I read an eARC of this book in the fall of 2025, and I devoured it in a day. Cordova and Olthoff are quickly becoming two of my favorite authors who have yet to let me down individually, and together - the sum is greater than the parts. I loved this joint effort between them; the characters are believable, and action enjoyable. I am looking forward to the continuation of the story of Blue and Tavi in the rest of the books in the Bronze Legion Series!
17 reviews
January 31, 2026
Stop. Buy this book. Read it!

Absolutely great book...a real joy to read. Well-developed characters, detailed plot and storyline, lots of action.

I cannot wait for the next installment!

Heartfelt thanks to both Melissa and Jason.
Profile Image for Iain.
22 reviews44 followers
Read
February 6, 2026
Exciting Read

I love it when a book.is so.good, I can't put.it down until.it's read and I immediately want to.read the next book in the series.
Displaying 1 - 11 of 11 reviews

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