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Undying Mercenaries #25
Hell World
Four hundred degrees! Toxic atmosphere! Gravity beams that crush men in armor like beer cans! Welcome to Infernus.
Legion Varus assaults an alien stronghold that's too close to Mother Earth. The battle turns into a meat grinder that chews through soldiers faster than revival machines can spit them out again.
When enemy reinforcements approach the star system, the campaign becomes a race against time. Centurion James McGill must defeat the Demons and their minions before it's too late. He teams with old friends and old enemies. Robots, Blood Worlders, and Saurians join the fight in a grand battle on a deadly planet.
Then McGill meets the entity that is behind the invasion, changing everything…
Hell World is the latest action-packed entry in B.V. Larson's bestselling Undying Mercenaries series.
Legion Varus assaults an alien stronghold that's too close to Mother Earth. The battle turns into a meat grinder that chews through soldiers faster than revival machines can spit them out again.
When enemy reinforcements approach the star system, the campaign becomes a race against time. Centurion James McGill must defeat the Demons and their minions before it's too late. He teams with old friends and old enemies. Robots, Blood Worlders, and Saurians join the fight in a grand battle on a deadly planet.
Then McGill meets the entity that is behind the invasion, changing everything…
Hell World is the latest action-packed entry in B.V. Larson's bestselling Undying Mercenaries series.
- GenresScience FictionAudiobook
Audible Audio
Published May 12, 2026
About the author
B.V. Larson
125 books1,564 followersBrian Larson is an American science fiction and fantasy author
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Displaying 1 - 30 of 41 reviews
August 22, 2026
3/5 ⭐ (I Liked It)
While I enjoyed this book...this 25th book, I found it to be one of the weaker ones overall. It was still enjoyable to get through, but I found myself nowhere near as invested as I have been in so many other books in this series.
The thing I didn't like as much was the campaign itself. There is usually a slew of interesting things that happen during each campaign, and while I wouldn't go so far as to say this one was uninteresting, I do think the overall campaign on Infernus dragged a bit.
The things I did like, though, were the beginning and the ending.
Normally, the beginning and ending of these books are pretty similar. McGill is chilling at home, someone comes to tell him about a new mission, and off we go. Instead, we get a little unique side trip this time, along with some more character development.
The ending, in turn, is usually some lady friend coming to his house and McGill getting to enjoy the ladies' enchantments and company. 😂 This time around, we get something that felt a little more touching. I appreciated the change. It was refreshing and well done.
While I came away a little disappointed overall with what I've come to expect from this series, it was still a fun and easy read. Twenty-five books in, that's saying something.
While I enjoyed this book...this 25th book, I found it to be one of the weaker ones overall. It was still enjoyable to get through, but I found myself nowhere near as invested as I have been in so many other books in this series.
The thing I didn't like as much was the campaign itself. There is usually a slew of interesting things that happen during each campaign, and while I wouldn't go so far as to say this one was uninteresting, I do think the overall campaign on Infernus dragged a bit.
The things I did like, though, were the beginning and the ending.
Normally, the beginning and ending of these books are pretty similar. McGill is chilling at home, someone comes to tell him about a new mission, and off we go. Instead, we get a little unique side trip this time, along with some more character development.
The ending, in turn, is usually some lady friend coming to his house and McGill getting to enjoy the ladies' enchantments and company. 😂 This time around, we get something that felt a little more touching. I appreciated the change. It was refreshing and well done.
While I came away a little disappointed overall with what I've come to expect from this series, it was still a fun and easy read. Twenty-five books in, that's saying something.
November 7, 2026
Seems like it’s been a while since I read one of these books and it has. I read “Demon World” in September 2025. But these books are still great books to read even after 25 of them. We’re still reading about the exploits of Centurion James McGill. He’s one of the most interesting Legion Varus soldiers that has attracted the attention of the Galactics on many occasions.
Yet, in this book all he wants to do is go fishing. There seems to be a huge catfish named Old Methuselah that’s swimming around in the swamp waters near McGill’s shack. This fish has been notoriously hard to catch by everyone that has tried. That’s why he’s called Old Methuselah; he’s lived a long time just swimming around in the Satilla River. But McGill is now ready to go catch the fish and end his way of life. Then his tapper starts going off!
Strangely, when McGill looks to see who’s calling and realizes that it’s Galina Turov, he wants to run into the swamp and go fishing. That’s strange since usually seeing Galina coming to his shack means he’s in for some wonderful night. But, McGill stands on his porch in his chest-high waders and asks Galina what she’s doing there.
What she tells him starts the both of them on a very strange trip. A long time ago, McGill had told Galina that she and he should go on a pleasure cruise one day. Just the two of them and not war-fighting or Hegemony slugs to worry about. Now Galina says she’s already booked them a cruise and they have to leave now! Strangely, McGill decides to go with her. He packs a small bag of clothes and then gets in Galina’s aircar. The only reason McGill does this is because Galina was begging him to go with her on this cruise. That’s not like Galina, she never begs, just orders mostly. So, something was up but she wasn’t telling right now.
So how does this result in McGill going to Hell World. Well, McGill and Galina have a history that caused Servant Alexander Turov, Galina’s father, some serious problems. One of which was when they freed Drusus from his brain-tank and now that individual has a new body and is the leader of a rebellion. Yet, Servant Turov isn’t ready to make McGill pay for that transgression just yet. No, he needs him to do some scouting. It appears that something resembling Silicoids and their crystalline drones are operating on a planet called Infernus and Turov wants to know the extent of their invasion. McGill is going on a scouting mission, probably one-way, but that’s of no concern to Turov as long as he gets the info he wants.
This is a typical situation for James McGill, except he doesn’t usually have to pay for his past transgressions, usually. So, McGill and a Saurian named Rassh are teamed up and teleported to Infernus. They are there just to scout the area and find out what is actually going on. When they had the information they needed, they were supposed to signal a pickup starship that would take them back to Earth. Of course, that wasn’t going to happen. McGill and Rash both find out just how violent and destructive the planet Infernus can be when they are both caught in a lava tube flowing with fresh lava.
Of course, McGill eventually gets revived with one of the mystical alien revival machines. He’s back at Central HQ and immediately finds himself arrested. It seems like the Galactics are now interested in some of McGill’s past activities which could very well result in his demise and the extermination of the entire human civilization! Typical McGill problems.
There’s a lot of fighting in this book, a lot of dying and of course being revived. Infernus is not very hospitable to human life but the mission must be completed at all costs. There’s going to be a lot of dying.
This definitely isn’t the last book in this series. Book 26, “Spawn World” is now available on Amazon. It’s on my reading list.
[Note 1 (12/23/2025): I’m no longer associated with Amazon and will no longer provide any links to books from that website. You can usually find books that you like at your usual source.]
[Note 2: As of 12/03/2023, this will not be posted on Amazon since I have been banned from posting reviews for some unknown reason. ]
Yet, in this book all he wants to do is go fishing. There seems to be a huge catfish named Old Methuselah that’s swimming around in the swamp waters near McGill’s shack. This fish has been notoriously hard to catch by everyone that has tried. That’s why he’s called Old Methuselah; he’s lived a long time just swimming around in the Satilla River. But McGill is now ready to go catch the fish and end his way of life. Then his tapper starts going off!
Strangely, when McGill looks to see who’s calling and realizes that it’s Galina Turov, he wants to run into the swamp and go fishing. That’s strange since usually seeing Galina coming to his shack means he’s in for some wonderful night. But, McGill stands on his porch in his chest-high waders and asks Galina what she’s doing there.
What she tells him starts the both of them on a very strange trip. A long time ago, McGill had told Galina that she and he should go on a pleasure cruise one day. Just the two of them and not war-fighting or Hegemony slugs to worry about. Now Galina says she’s already booked them a cruise and they have to leave now! Strangely, McGill decides to go with her. He packs a small bag of clothes and then gets in Galina’s aircar. The only reason McGill does this is because Galina was begging him to go with her on this cruise. That’s not like Galina, she never begs, just orders mostly. So, something was up but she wasn’t telling right now.
So how does this result in McGill going to Hell World. Well, McGill and Galina have a history that caused Servant Alexander Turov, Galina’s father, some serious problems. One of which was when they freed Drusus from his brain-tank and now that individual has a new body and is the leader of a rebellion. Yet, Servant Turov isn’t ready to make McGill pay for that transgression just yet. No, he needs him to do some scouting. It appears that something resembling Silicoids and their crystalline drones are operating on a planet called Infernus and Turov wants to know the extent of their invasion. McGill is going on a scouting mission, probably one-way, but that’s of no concern to Turov as long as he gets the info he wants.
This is a typical situation for James McGill, except he doesn’t usually have to pay for his past transgressions, usually. So, McGill and a Saurian named Rassh are teamed up and teleported to Infernus. They are there just to scout the area and find out what is actually going on. When they had the information they needed, they were supposed to signal a pickup starship that would take them back to Earth. Of course, that wasn’t going to happen. McGill and Rash both find out just how violent and destructive the planet Infernus can be when they are both caught in a lava tube flowing with fresh lava.
Of course, McGill eventually gets revived with one of the mystical alien revival machines. He’s back at Central HQ and immediately finds himself arrested. It seems like the Galactics are now interested in some of McGill’s past activities which could very well result in his demise and the extermination of the entire human civilization! Typical McGill problems.
There’s a lot of fighting in this book, a lot of dying and of course being revived. Infernus is not very hospitable to human life but the mission must be completed at all costs. There’s going to be a lot of dying.
This definitely isn’t the last book in this series. Book 26, “Spawn World” is now available on Amazon. It’s on my reading list.
[Note 1 (12/23/2025): I’m no longer associated with Amazon and will no longer provide any links to books from that website. You can usually find books that you like at your usual source.]
[Note 2: As of 12/03/2023, this will not be posted on Amazon since I have been banned from posting reviews for some unknown reason. ]
July 3, 2026
More of the same
Book 25 and they are slowly but surely becoming so similar that the only difference is the world where the legionnaires end up fighting some new alien
Some of the background politics evolves, but it's slow. Servant Turov is doing his usual power plays and even those are similar each time
Not sure how the author gets out of this rut. McGills ability to be reborn, along with every other legionarie, just means it all stays the same, with no need for change
The relationship with Galina is obviously progressing at last, hopefully that changes things
If you read this as a standalone book, or even 1 of a few in the series you'd easily rate this 4*, but per the earlier comments it's a weak 3* from me
Book 25 and they are slowly but surely becoming so similar that the only difference is the world where the legionnaires end up fighting some new alien
Some of the background politics evolves, but it's slow. Servant Turov is doing his usual power plays and even those are similar each time
Not sure how the author gets out of this rut. McGills ability to be reborn, along with every other legionarie, just means it all stays the same, with no need for change
The relationship with Galina is obviously progressing at last, hopefully that changes things
If you read this as a standalone book, or even 1 of a few in the series you'd easily rate this 4*, but per the earlier comments it's a weak 3* from me
April 8, 2026
Good Read
McGill is facing being permed. A Galactic tribunal has been convened facing charges of killing Galactics of various species, working with rebels, stealing Galactic items, visiting Galactic worlds, etc., but it doesn’t stop there! Oh no! His crimes are so severe that the Galactics having taken notice also noticed humanity expanding to establish distant colonies against Galactic rules which calls for the complete annihilation oh the human race! No wiggle room of Ol’ McGill on this one! But it is James McGill we’re talking about. It’s about to get very interesting for James and Humanity!
McGill is facing being permed. A Galactic tribunal has been convened facing charges of killing Galactics of various species, working with rebels, stealing Galactic items, visiting Galactic worlds, etc., but it doesn’t stop there! Oh no! His crimes are so severe that the Galactics having taken notice also noticed humanity expanding to establish distant colonies against Galactic rules which calls for the complete annihilation oh the human race! No wiggle room of Ol’ McGill on this one! But it is James McGill we’re talking about. It’s about to get very interesting for James and Humanity!
May 11, 2026
Larson has lost interest and gotten lazy with this series. Endless plot holes, inconsistencies, logical fallacies, and lack of any sort of depth. It was almost as though he created an outline and had AI finish it or had someone else throw it together.
The first dozen or so books in this series were fantastically entertaining. Then they became extremely predictable, but still entertaining. Now they are predictable, shallow, lacking any logic in characters actions and motives other than the most basic. Like the last few books, it just felt lazy and rushed. B.V. either needs to give the series up or give it the attention it needs. This will probably be the last book I read in this series.
The first dozen or so books in this series were fantastically entertaining. Then they became extremely predictable, but still entertaining. Now they are predictable, shallow, lacking any logic in characters actions and motives other than the most basic. Like the last few books, it just felt lazy and rushed. B.V. either needs to give the series up or give it the attention it needs. This will probably be the last book I read in this series.
July 4, 2026
Just realized these stories are very formulaic. They got less enjoyable, and this one was no exception. There were some humorous moments though along with frustrating ones. The most frustrating scene was where McGill was trying to tell Graves and Winslade about the second crystal. I was just thinking to myself: Well, you reported it. Just walk the f**k out. But nooo… his superiors are trying to tell him it’s all in his head. They were relating to his experiences with women. And then the author had McGill argue a moot point. It was a pretty frustrating read for me. I had to skip past some of it.
April 10, 2026
these books are best spaced apart by at least a few months. otherwise you notice the repeated plots and scenes between books.
it is sad that the most interesting characters serve to just either be a comedic foil or sexual conquest for mcgill.
also after 25 books the copy editor must be getting really tired!
"He soon drowned. It didn’t even take that long. Maybe I hadn’t given him a chance to get a good, solid breath before he went under."
"Collins had been assigned to ride herd on the robot operators for a scouting mission."
it is sad that the most interesting characters serve to just either be a comedic foil or sexual conquest for mcgill.
also after 25 books the copy editor must be getting really tired!
"He soon drowned. It didn’t even take that long. Maybe I hadn’t given him a chance to get a good, solid breath before he went under."
"Collins had been assigned to ride herd on the robot operators for a scouting mission."
April 17, 2026
Very repetitive, if you read any of the first 24 books in the series, you've read this book too. Suffers from small cast syndrome, and did I say repetitive? Whilst McGill was finding his way, moving up the chain of command there were interesting events occurring in the series, but this was long ago, and now it is same old same old, boring. Annihilation coming, send Varus, baddies on the horizon, send Varus, what happened to the many legions mentioned earlier in the series? And enough with the octagenarians running things. Find a way to perm a few so that we can get away from the boring small cast syndrome. Watching grass grow would be a positive alternative to reading yet another book in this series unless the author can move the story forward and with that goes change in the characters, fresh people and what of the core? And no Claver!
This entire review has been hidden because of spoilers.
April 18, 2026
Praise for McGill!
Somehow, he finds a way to keep winning. I’d be kinda nice if he and Galina worked out something semi-permanent. It’s obvious they have a thing for each other. Maybe future missions could have them working more as a team rather than ‘cause and effect’. There’s a number of possibilities there, even more covertly. Good writing, good humor, definitely captures military attitude. Keep up the good work!
Somehow, he finds a way to keep winning. I’d be kinda nice if he and Galina worked out something semi-permanent. It’s obvious they have a thing for each other. Maybe future missions could have them working more as a team rather than ‘cause and effect’. There’s a number of possibilities there, even more covertly. Good writing, good humor, definitely captures military attitude. Keep up the good work!
May 11, 2026
It Is Time For McGill…
I just love this series! I always preorder now and sometimes I’ve gone back to reread them. The author’s ability to come up with twists to keep it fresh and funny is amazing. However, it is time. Time for what you say? Time for McGill to get married and have kids! I think Mrs. Galina Turov McGill would be fine revenge on the Servant, don’t you? And McGill’s mom would love another grandbaby too…
I just love this series! I always preorder now and sometimes I’ve gone back to reread them. The author’s ability to come up with twists to keep it fresh and funny is amazing. However, it is time. Time for what you say? Time for McGill to get married and have kids! I think Mrs. Galina Turov McGill would be fine revenge on the Servant, don’t you? And McGill’s mom would love another grandbaby too…
Read
May 11, 2026the best writing yet
Thank you this was the best writing of the series literally fantastic, I'm not sure if every one felt this I hope you did it. Please continue to write in this style. Great read great science fiction great story i know you've been doing James for a long while but this was the most thoughtful and added the necessary depth to his character. Thank you the best read yet
Thank you this was the best writing of the series literally fantastic, I'm not sure if every one felt this I hope you did it. Please continue to write in this style. Great read great science fiction great story i know you've been doing James for a long while but this was the most thoughtful and added the necessary depth to his character. Thank you the best read yet
April 6, 2026
Twenty five books in and the formula keeps working.
What can you say about a series you are 25 books deep into?
The formula works. I love this series. And this book in particular leaves some surprisingly good feelings in its wake.
In a lot of ways, the larger story of the series keeps drawing me in, while the War Of The Book is always reasonably novel and interesting.
What can you say about a series you are 25 books deep into?
The formula works. I love this series. And this book in particular leaves some surprisingly good feelings in its wake.
In a lot of ways, the larger story of the series keeps drawing me in, while the War Of The Book is always reasonably novel and interesting.
July 6, 2026
This series is just a comfort listen for me, like a mindless sitcom. Every book is basically the same and the overlaying story arc is going absolutely nowhere.
This book seemed to develop James' relationship with a couple of the usual characters, I wonder whether B.V.Larson is changing the direction of the series to have James start forgiving his enemies.
This book seemed to develop James' relationship with a couple of the usual characters, I wonder whether B.V.Larson is changing the direction of the series to have James start forgiving his enemies.
April 1, 2026
Another good one in a good series
An interesting new world for McGill to fight and die on. Some interesting new interactions with old goes. Well worth a read. Looking forward to the next one.
An interesting new world for McGill to fight and die on. Some interesting new interactions with old goes. Well worth a read. Looking forward to the next one.
April 3, 2026
Refined
Possibly the best chapter yet in Magills series. The writing has matured and there are no remaining remnants of the book a few books ago that seemed to have used AI in part. Not just slogging it out in battle but addressing other parts of his life. A good read!
Possibly the best chapter yet in Magills series. The writing has matured and there are no remaining remnants of the book a few books ago that seemed to have used AI in part. Not just slogging it out in battle but addressing other parts of his life. A good read!
April 4, 2026
Hell World A++++++ and then some
Book 25 holds its own! I came away with the feeling this story is not yet told. Looking forward to that next book and the fight that must resume to extreminate the nanites and the worms. Otherwise it will be us......
Book 25 holds its own! I came away with the feeling this story is not yet told. Looking forward to that next book and the fight that must resume to extreminate the nanites and the worms. Otherwise it will be us......
April 9, 2026
Tired she boring
I enjoyed these at the beginning, but they are tired and boring now. Formulaic, and just not very creative - because they're all essentially the same book. Time to put this series to bed.
I enjoyed these at the beginning, but they are tired and boring now. Formulaic, and just not very creative - because they're all essentially the same book. Time to put this series to bed.
April 9, 2026
just getting better
The last few Undying Mercenaries books have shown a slow growth to McGill that I like. Sooner or later with his experience he has to start thinking about the bigger picture. I’m glad to see some thought penetrating that thick skull!
The last few Undying Mercenaries books have shown a slow growth to McGill that I like. Sooner or later with his experience he has to start thinking about the bigger picture. I’m glad to see some thought penetrating that thick skull!
April 11, 2026
Great Read, the great McGill
As always, very enjoyable. A new world, maybe “Fantasy World” where the galactics go to vacation but it is invaded and there are many important hostages but McGill can’t leave based on his current pardon boundaries but he is what is needed.
As always, very enjoyable. A new world, maybe “Fantasy World” where the galactics go to vacation but it is invaded and there are many important hostages but McGill can’t leave based on his current pardon boundaries but he is what is needed.
April 25, 2026
Another awesome McGill story!
Keeping it interesting with another James McGill adventure. I love the direction the series is going and look forward to enjoying the journey as James makes his way to the top.
Keeping it interesting with another James McGill adventure. I love the direction the series is going and look forward to enjoying the journey as James makes his way to the top.
April 27, 2026
Its not that I didn't enjoy this book. Its more that the whole series is getting a bit stale. McGill has been a Centurion for about 15 books now. Its the same basic story being rinsed and repeated. There needs to be something different and soon to freshen it all up.
June 11, 2026
Hell to pay!
Another great adventure in the life and times of James McGill! I particularly liked the character interactions. Mr. Larson has an amazing imagination and writing style that makes me look forward to the next installment. Thank you.
Another great adventure in the life and times of James McGill! I particularly liked the character interactions. Mr. Larson has an amazing imagination and writing style that makes me look forward to the next installment. Thank you.
June 22, 2026
The gang is back
McGill, Harris, Sargon, Manfred, Carlos.
Need I say more?
A fun read as always, there were a few moments where I genuinely laughed out loud.
I love this series and always will.
McGill, Harris, Sargon, Manfred, Carlos.
Need I say more?
A fun read as always, there were a few moments where I genuinely laughed out loud.
I love this series and always will.
July 26, 2026
Ok actually sweet romance
Actual romance in this book actual growth in a relationship. I was surprised. Also, usual combat we love.
Read the last chapter first for something nice.
Actual romance in this book actual growth in a relationship. I was surprised. Also, usual combat we love.
Read the last chapter first for something nice.
October 15, 2026
Repetitive, derivative, moderately mysoginistic. This series, as I have said many times, is bad. Yet here I am, 25 books in, and still reading them. I'll be here to leave a poor review of 26 as well if I am being honest. What is wrong with me?
March 30, 2026
excellent as always.
This series is my favorite of all the series I read. Love it Always preorder books by this author. Look forward to next
This series is my favorite of all the series I read. Love it Always preorder books by this author. Look forward to next
April 5, 2026
Another Hit
Another great book in the series. Enjoyed all of McGills antics. Looking forward to the next book in the series.
Another great book in the series. Enjoyed all of McGills antics. Looking forward to the next book in the series.
April 6, 2026
prison world
I really enjoy McGill’s antics in the series so far I could just imagine him going to prison and just taking it over.
I really enjoy McGill’s antics in the series so far I could just imagine him going to prison and just taking it over.
April 11, 2026
Somehow he keeps producing
This book was really good. I love how past characters come back at random in these books. The end was... Actually heart warming. Y'all know James 😂
This book was really good. I love how past characters come back at random in these books. The end was... Actually heart warming. Y'all know James 😂
April 12, 2026
was and kindness
You will be in the shit of battle and find your kindness will make for a bright spot in your memory.
You will be in the shit of battle and find your kindness will make for a bright spot in your memory.
Displaying 1 - 30 of 41 reviews