Warhammer 40,000: Gladius – Relics of War: Guide to Beating Impossible Difficulty – Space Marines: The Codex Astartes, Gladius Edition

“Give me a hundred Space Marines, and I can conquer a world.”
There’s a reason the Space Marines are the tutorial faction. Playing as the Astartes lets you avoid a lot of the more complex concepts in Gladius…you barely have to think about starting city placement, the units are sturdy and well-balanced, loyalty is essentially a non-issue, there’s less resources to worry about, etc.
However, this simplicity works against them, particularly in the late game. This guide will help you stay ahead of the ever-proliferating AI as you build your single city to magnificence.
Don’t want to read this absurdly long guide? Go straight to the “Brief Summary” section for the most important points.

Please refer to my General Impossible guide for non-faction specific advice on beating this difficulty. (The guide you’re reading now will focus on strategy which is meant for the Space Marines specifically, particularly where it may contradict the general advice.)
https://steamcommunity.com/sharedfiles/filedetails/?id=3000649357

Here is my Ork-specific guide:
https://steamcommunity.com/sharedfiles/filedetails/?id=3029674153

Or if you’d rather play with tanks:
https://steamcommunity.com/sharedfiles/filedetails/?id=3067031734

And if you’re not afraid of the Dark Gods:
https://steamcommunity.com/sharedfiles/filedetails/?id=3051622207

Dying race? Not if you have anything to say about it!
https://steamcommunity.com/sharedfiles/filedetails/?id=3343149132

The Space Marines are a moderately good choice to beat Impossible difficulty, but require a lot of planning to compete with the AI’s enormous production in the end game.

Just one city. With no second or third city to worry over, you can focus your attention on expansion and production in your mighty capital and you’ll never have the multi-city loyalty tax.

Hardy units. Nearly all of the Space Marine units are tough, with plenty of health and armor. The Chaplain may well be the single best defended unit in the game (after adding items to his roster), and even the starting units can deal and receive damage with alacrity.

No loyalty issues. You can play a whole game without ever building a loyalty building (as long as you invest in Chaplains) and you’ll only have minor penalties to deal with. On Impossible you’ll want to build them just for the overall production boost, but it’s nice to not be constantly scrambling to keep your citizens in line.

Less resources to manage. Requisitions replace both food and ore, so that’s one less production building to juggle.

No negatives on map tiles. Most factions have some map tiles which reduce resource production of a certain type (less food in the arctic, for example). Not so for the Space Marines, who are adapted to all environments!

Excellent mobility. With technology, most units can drop anywhere on the map. This extends to fortifications like the Macrocannon, meaning that you can secure an advanced area in a single turn.

Highly dependent on DLCs. I’m going to lead with this one, because it really annoys me. The Space Marines are Warhammer 40k’s signature faction, but their most crucial end-game units are locked behind DLC. Without DLC, you’ll feel tough until the beginning of the end-game, and then suddenly you’re facing Brass Scorpions with Vindicators. That’s right, no Land Raiders, Macrocannons, or Devastator Centurions. I can’t even begin to figure out a strategy for this faction without those units…

Just one city. Yes, yes. It’s an advantage and a disadvantage. Without additional cities, your map control is limited, and you can’t build specialized cities to hyper-produce a single resource. You can also only produce one unit of each type per turn, which isn’t *usually* a problem…

Requisitions dependency. It is incredibly easy to paint yourself into a corner with requisitions! For most factions, you build and support infantry with food, so it doesn’t prevent you from constructing buildings. For the Space Marines it’s all too easy to not be able to afford a requisition building simply because your unit upkeep is eating all your production. I will spend a decent portion of this guide trying to keep you out of this economic death spiral.

Infantry-heavy armies. Infantry are fun, and appropriate for the Angels of the Imperium. However, groups of “models” (e.g. Tactical Space Marines) degrade as they are wounded, whereas single-model units do not (e.g. Predators). In practice, this can mean that your brilliant assault suddenly falls apart as your units break down and do less damage.

Reliance on Fortresses of Redemption. I love the concept here…fortresses which expand your borders and bolster your economy without much management. However, at the beginning of the game they are quite vulnerable and can be destroyed by wildlife, potentially crippling your economy. This is especially true on the creep-dense maps that I most enjoy.

One way tickets. You can easily do an orbital drop anywhere. Getting back is another thing entirely. This particularly affects co-op play, but can be a solo problem if your home base is surprised while your best units are deep in the field.

We’ll use the settings mentioned in the general guide, with some exceptions: Turn down Tropical and Volcanic terrain one step, and increase Desert and Arctic one step. This is because Tropical and Volcanic provide no bonuses for the Space Marines.
Any opposing faction will work; I usually use Tyranids or Chaos to get the “good vs. evil” vibe (at least as far as Warhammer has those qualities 😊 ) However, you can beat any opponent with this faction.
I recommend leaving the story turned on…it’s almost a mini-tutorial as following the story will reward you for doing the things you should be doing anyway. It’s also easy to exit from the quests before they get too distracting.

I prefer to play Gladius with a friend against the AI, but I always try my strategies solo to make sure they’re effective. Everybody pairs well with Space Marines (because of the Marines’ mobility and variety. Additionally, they can heal all units, both biological and mechanical. This helps offset some of the disadvantages of factions like the Aeldari (who have very limited healing) and the Sisters of Battle, who struggle to fix their machines.
In co-op, you’ll want to prioritize Orbital Deployment so you are ready to help your ally if the enemy factions suddenly appear.

Your starting city location is important with the Space Marines, but it is affected by different elements than with most other factions for several reasons:

• Volcanic and Tropical terrain provide no modifiers.
• Most of your resource boosts will eventually come from Fortresses of Redemption, not your main city.
• You don’t have to worry about placing it in a way which affects second or third cities.
• You are essentially placing two sites at once—the city itself and the first Fortress of Redemption.

When placing your city, certain early boosts can really help avoid early shortages, in particular the “Requisitions Trap.” I have experimented heavily with city site locations, and have found that poor starting locations seem to have more effect than with any other faction. Consider the following when selecting where to drop your city:

• Your city is unique in that it can expand to range 4. While you won’t need all those tiles, you will need a lot of them. Don’t build near water, which can deprive you of much-needed land…remember, there’s no second city!
• Your Great Hall (the city center) is nearly unique in that it produces 12 requisitions, not the usual 6. This means that any early multipliers for requisitions will be much more effective.
• While you don’t have to worry about second cities, you do need to think about placement of your Fortresses of Redemption. If an outpost is within four tiles of your city center, you can eventually grab it through expansion…for maximum efficiency place your Fortresses to seize outposts outside this four-tile radius. (The very best placement would have the Fortress inside the city radius but controlling an outpost outside the city!)
• Here’s an advanced mechanic that has helped me in the early game: when the game starts, there’s a visible circle of terrain on the map. This area is completely free of hostile neutrals, which makes it perfect for a Fortress of Redemption. If you place the city near the edge of the visible area, it can easily handle any annoyed locals while the Fortress can be safe in the middle of the starting circle.

I’m going to spend more time than usual on the topic of the starting city since I’ve found it to be so critical for the Space Marines. Remember that I’m playing with maximized outposts and neutrals which gives many opportunities for Fortresses but they are highly vulnerable to creep attack. These games are intense from the beginning!

In the image, I’ve shown an early game picture of my starting city, which (after 20 or so partial starts) has turned out to be as close to ideal as I’ve seen. The image is supremely busy because I’ve turned on resource display (ctrl-Z), which is intolerable during the game but very helpful for city planning.

Why is this spot so great?

• The starting area is built at the bottom left corner of the world map which keeps me from being surrounded by hordes of neutrals. More central locations become a grinding war of attrition.
• My Great Hall was constructed at the lower right edge of the original visible circle of tiles. I purposely placed it so that there is a requisition Outpost five tiles away, perfect for my first Fortress of Redemption.
• The placement is free of cliffs and water which would hem in my city growth and make unit maneuverability challenging.
• The starting tile is desert, which gives +20% to energy. It’s next to a Ruin of Vaul, which gives a further +20% to science, and the terrain contains rocks, which adds +20% to those all-important requisitions. +60% is about as good as it gets for a starting location, and it’s the three most limiting resources in the early game.
• The Ruin of Vaul sits in arctic terrain, which means I have early access to a +40% research tile. A Shard of Vaul is just to the north, and so I can build my first unit buildings on a tile which will build them faster. My second orbital relay can also take advantage of the bonus. Finally, to the east is a Grox Pasture, which will quickly enhance my requisition production and gives me a buildable tile with a 40% boost to requisitions.

In summary, this is about as perfect a starting location as I can imagine. Since I can only ever build one building at a time in my single city, I want those buildings to be maximally efficient so that I don’t have to build too many of them. I can easily avoid a requisitions trap because I start with the extra 20% requisitions and have multiple nearby tiles which will further enhance this bonus.
The Marines can easily fall behind in research production (even here I’m slightly behind my ‘par’), but my supreme research start should make that easy to correct and I shouldn’t ever get to a point where my lack of research limits my builds. In this game, I was producing 55 research by turn 40, so I had fully caught up with my goals.

Early goals are to build a solid base of Requisitions, and try to get some research flowing. Unique to the Space Marines, you need to be hunting for great sites for your Fortresses of Redemption. Ideally, you’d have these sites picked out and cleared before the cooldown expires, and then you can drop the Fortress in and immediately reap the benefits.

The build order from the general guide works fairly well…substitute Fortresses of Redemption for second cities, however. I’ve added some specific notes below.
First, acquire the best research tile you can, and build the research building on it. (For most factions, having your research output equal to the turn number is “par.” This is true for the Space Marines…eventually 😊)
Then, build an Apothecarion (the infantry building) so that you can clear and protect sites for your Fortresses. Tactical Space Marines are very, very good starting units. Move them slowly outward to set overwatch traps, and let the enemy come to you…they excel when Bolter Discipline is active (which is when you haven’t moved) because they do full damage at range two and can shred annoying creeps like Stingwings. Remember that the Fortress of Redemption is a military unit as well, and can help strengthen your hold on an area.
Space Marine unit buildings are good at multitasking…for example, the Apothecarion provides both a small research boost and an increase in the population cap. These are both very important in the early game.
Next in the build queue: the hero building. The Captain is incredibly tough and can self-heal which makes him a great leader to send in to unexplored areas and soak overwatch. He’s also a critical investment…see the “Heroes” section of the guide.
Wait on the vehicle building…early Space Marine mechanized units are durable but not particularly well-suited for clearing your surroundings, and you’re better off with a hero building.

I hope to help you dodge a pitfall which can completely ruin your game without ever contacting the enemy…the requisitions trap. If you fall into it, you will probably have to restart your game, but not until you’ve endured ten rounds of frustration. I am not speaking hypothetically here 😊

[/h3]So what exactly is the trap?[/h3] Because you need requisitions to build and maintain all units and all buildings, you can get into a position where you literally cannot rescue yourself. Here’s how it happens: You’re happily following the guide, building Apothecarions and a couple of Space Marines, and then your hero building and Captain. Then you try to be clever and build a new Assault Marine.
Suddenly, as the Marine strides out proudly, you glance up and realize that you just spent yourself down to 14 requisitions, and you have an income of 2. Now, you don’t have enough to build the requisition building! This means you are completely locked out of new buildings or units in your city.

At first, you try to eke it out by letting that meager income accumulate until you can buy the Refectory, three or four turns later. Then, you spend it all on the building. Now you’re a little better, but still in the single digits. Again, you wait, accumulate, and spend it all again on a requisitions building. You’re finally out of the hole…after fifteen turns of zero productivity. You utter some curse in High Gothic, and restart the entire game, because your autosaves are far too recent to help you.
It’s almost better to find yourself in a negative requisitions state because then at least you know the situation is irreparable and you don’t waste so much time.

Don’t let your requisitions income fall into single digits! Keep enough in storage to be able to build a Refectory at a moment’s notice. Don’t build units you can’t afford. Prioritize ore fields and grox pastures when you’re placing Fortresses. And play with the story quest active, because it will keep a constant reminder of your requisitions income on your screen until you complete it.

You start with two Space Marines; they are hard to kill but easy to disable. Keep them at full health so they can kill the neutrals efficiently. Do *not* lose these units. If you need to save scum, then do it! Early mistakes will compound over time to substantially hurt your later game. Heal them often…they will heal twice as fast in your city tiles, but a Compound will also give a bonus. Tactical Marines are so powerful that you should build at least two to supplement your initial units…a band of Tactical Space Marine units can outmatch almost all of the wildlife on Gladius, as long as you keep a respectful distance from Umbra and Kastelan Robots.

Keep the Marines together to allow you to kill hostile units rather than slivering them. It’s really frustrating when you get those Stingwings down to a single health point, but then they run off and heal. Later, you’ll see your “safe” compounds captured by the same critters. Set up overwatch traps in forests next to captured compounds; Stingwings and Cultists find the outposts irresistible, and you can get a free attack when they try to reclaim the compound. Don’t wander too far from your Fortresses which can find themselves quickly surrounded and destroyed by a determined group of neutrals.

Fortresses are absolutely critical to your early game, so don’t let them fall. Consider turning off overwatch so they don’t accidentally attract the attention of a wandering Umbra or Kastelan Robot…their lasers aren’t that effective and have a very long range, so this happens more commonly than you’d like.

For some factions (like Chaos, or the Astra Militarum), the city itself is an excellent military unit, capable of slivering or killing most of the early neutral units. Yours is merely mediocre, and often finds its firing arc blocked by its own city. Keep at least one Marine nearby to chase off any neutrals which want to camp directly where you’re trying to build that Refectory.

Finally, be happy with owning 6 or 7 compounds in the early game. Haring off into the wilderness to grab that tempting Jokero trader is a sure way to get isolated and killed. Once you have four Tactical Marines and a Captain, you can get more adventurous.

You’ll be tempted to always go for the highest-level technology you can afford, but don’t fall into this trap. If an early technology will help you right now, then take it! Usually, the time cost is low, and overflow research points aren’t lost, so it may not even slow you down at all. A good example is Tactical Doctrine, which tremendously improves your starting units at a low cost.

The first priority is getting a working economy, so I open with the Reclusiam so I can get my first Captain into the field to start earning influence. Next is Frag Grenades which are effective against those pesky groups of weak neutral units in the early game.
Tactical Doctrine has essentially replaced my need for other early Space Marine units because it makes your baseline Marines so strong. Don’t research it until you can afford the influence cost, but then make it a priority. Eventually you’ll need all the Tier 1 technologies, but move up to Tier 2 for now.

I usually take Dormitories next because otherwise you’ll run into a wall on your growth rate. Krak Grenades aren’t great for most circumstances, but they provide yet another upgrade for those all-important Tactical Marines.
The Chaplain is a just plain awesome hero, but you probably can’t afford to build him for awhile if you’ve built a Captain and bought him a Tantalizing Icon. Assault Space Marines are very good in close combat, but they aren’t helped by Tactical Doctrine and they tend to get wounded and spend a lot of time recovering.

Fortress Expansion is the lowest-Tier city expansion technology in the game. You’ll need it to boost your production from your existing buildings because you can only build one at a time. Then it’s Company Chapels…you probably won’t need a loyalty building yet, but you need to be ready when you do. The Librarian can wait…he’s not bad for a support unit, but you have other priorities.
If you don’t have Tactical Doctrine, now’s the time to get it, then move up to Tier 4.

Devastator Space Marines are a very strong range-3 unit, but long range isn’t as much of an issue for the Space Marines (as opposed to the Aeldari, for example), who function very well at range 2.

seems to have good stuff for all the factions. You really, really need the Orbital Relay (the “building building building”) so that you can finally start churning out new buildings with some speed. Research this first, and then build it now. For the Marines, the Orbital Relay also provides 6 influence at a time when you probably need it.

After that, research Kraken Bolts to continue the trend of improving your baseline Tactical Marines. At this point, they can one-shot some of the neutral groups and heavily damage the rest. You can even send your squad against Kastelans and Umbra, although you’ll have to spend time healing afterwards until you have Apothecaries. Melta Bombs are a surprisingly powerful upgrade, but they have very few appropriate targets. Ultimately I make these a priority if I’ve encountered a lot of Kastelans, and I skip it otherwise.

Did someone say Predators? One of the very best Tier 4 units, no question…*after* they get extra heavy bolters. Probably okay to wait on these guys, unless you just need a tank fix.

At this point, consider spending a few turns filling in technologies from earlier tiers…they should be very quick to research, and then they’ll be ready when you are.

Heroes are important to the Astartes, probably more so than for most factions…Captains and Chaplains hold the keys to your economic growth.

Move your heroes first each turn! Particularly the Chaplain; you’ll feel like a heel if you could have used Rites of War to buff a bunch of units, but you forgot to select him until everyone had already attacked. “I’ll remember next turn,” you tell yourself. But will you? I didn’t 😊
Heroes really shine when they are kitted out properly from the Jokero encampment. I send each new hero to a Jokero encampment immediately to purchase a Tantalizing Icon. This spooky object will add 8 influence per turn, which will more than offset the maintenance of each hero, and will act as an investment to buy future items.

Other must-have artifacts include the Zoat Hide Jerkin, and the Adamantium Weave Vest. Because your armor is so high, the vest is less critical…armor values over 10 don’t improve damage resistance, but they do help mitigate armor piercing enemies.
Dusk Blades are helpful for your Captain and Chaplain as they will self-heal any minor damage from creeps. Once you have extra influence to spend, give your Librarians the Uncreator Gauntlet, which can give you much-needed repair abilities for your vehicles. Note that there is no limit on the number of Gauntlets! (Lore note: The Gauntlet is a piece of techno-magic which allows the Mechanicus to reverse engineer technologies by reversing the flow of time and causing them to disassemble.)

Space Marine Captains act just like they should…you can charge them in ahead of your Marines so they can absorb overwatch and swipe with their electric swords, and then follow up for the kill.
They have four abilities, three of which are nice, and one of which is essential.

Deeds of Glory should be the first upgrade you choose, and you should level it whenever you can. This power grants a little bit of Orkiness to your faction, letting the Captain earn influence every time he gains experience…note that unlike the Orks, he does not need to strike the unit to gain the influence.

When maximized, this influence bounty can be 15-20 per kill. When combined with the Icon, the Captain can be the equivalent of having 2-3 Assimulara (influence buildings) in your city. As I’ve emphasized, you want to reduce the numbers of buildings you need as much as possible to lower the load on your building production.

Just an excellent overall hero, vying for the “best in game” title with the Tank Commander. He hits hard, including roasting multiple model units, and has an outstanding healing power. In addition, he provides a huge loyalty boost with Dogma Astartes, eventually the equivalent of two Company Chapels (not coincidentally). This ultimately means that you can stay in positive loyalty for the entire game with just Chaplains and one or two Chapels.

His Rites of War offer a solid damage boost, and the Canticles of Wrath are perfect for demoralizing your enemies before hitting them. But the Oration of Restoration must be quite a sermon, because it’s the best heal in the game. Not only does it have a radius, (i.e. the Chaplain heals everyone around him), but it persists for two rounds, healing a total of 18 points and offsetting future damage accrued by even full-health unit who charge into battle inspired by his other powers.
Finally, the good Chaplain is one of the most damage resistant units in Gladius, exceeded only by some specialized Drukhari units. His baseline armor is ten, which is boosted to eleven by the Extra Armor technology. If you want to take it to absurd levels, then give him the Vest and the Armaplas Bracers, and he ends up at 14, which means that no physical weapon in the game can fully pierce his armor. Not enough for you? He also has 50% hero damage reduction, and 50% invulnerable damage reduction from his Rosarius trait (he also has Terminator armor, but it doesn’t add to the Rosarius protection).

What does this mean in combat? If he’s at the edge of city under siege and benefiting from city damage reduction, I’ve seen him survive twenty separate attacks from enemy forces in a single turn. For him, the Zoat Jerkin is essential because that three extra health becomes the equivalent of about 20 for a normal unit.

Not critical to your strategy, the Librarian is a balanced support hero who won’t die too easily and can provide some assistance in combat. I mainly use him as a mule to carry items from the shop either for himself or to give to other heroes.

Telekine Dome makes a very dramatic bubble on the map, but it’s of mixed value. It stops ranged damage effectively but also works for enemies. This means that melee enemies can get inside the dome and become very hard to kill while having no negative effect on their own attacks.

Objuration Mechanicum provides a decent anti-mechanized ranged attack.

Shock Wave hits everyone around the Librarian, but this requires him to be where he shouldn’t, which is surrounded by enemies.

Levitate makes him the speediest infantry unit in the faction. This is why I combine it with a Faolchu’s Wing to make him the best item courier in the game. His armor means he’s not likely to be killed while carrying all his valuables along the way.

In a twist on the usual mechanics, middle game management is actually simpler than the early game for the Space Marines.

As soon as you can, build that Orbital Relay, and even consider a third soon after. Building production is a major choke point for the Marines and each relay gives anther 6 influence per turn.
Keep finding spots for those Fortresses…the price goes up slowly, so make sure you save enough influence to buy them when the cooldown expires. Occasionally, you’ll see a spot which is adjacent to two outposts…these are a premium, as they essentially give you a free Fortress with no cooldown (this only happens if you have the densest game settings for Outposts).

Where to put those fortresses? Requisition production is never wrong. Energy is second place as a perennial good choice, with influence and loyalty outposts tied for third.
Research outposts are very valuable in the early game, particularly if you have a research-poor starting location. Don’t build too many, though, as they become redundant…aim for 3, plus or minus one depending on your city’s output.

Fermentation pools can be great in the middle game because your orbital relays can build quickly, and each new building needs to be staffed. I feel that one Fermentation Pool is a minimum…remember that population growth needs to reach 30 to produce a citizen, so an output of 20 will give you two population every three turns. This is a decent “par” to consider if you’re not sure exactly what to do.

Keep your population limit at least six points higher than your current population. Hitting a population cap is a quick way to stonewall your city growth. Fortunately, if you’ve got 3 orbital relays you can fix this in a turn.

At this point you are probably doing fairly well in resources. Keep everything in positive balance, but focus on expanding requisition production, with roughly 150 per turn as a goal. This will allow you to build something from each “production line” every turn (i.e. aircraft, heroes, mechanized, and infantry). You may not need to do that right away, but if the AI comes knocking, you’ll need all the help you can get.

Expand your empire!

Strategically, stay to the edges of the map to avoid meeting the AI too early, and clear any corners behind your cities so that you have some compounds adding to your economy even during the invasion.

Tactically, lead with your Captain or Chaplain to absorb overwatch, and follow with infantry units to kill slivered enemies or take unguarded compounds. Artifacts (the spinning tetrahedrons) are like gold, and should be prioritized. The Siren Caster is my usual favorite for its loyalty boost to all cities, but the Marines barely benefit, so in this case I think they’re all roughly equal in value.

Be thorough at clearing creeps as you move. You’ll notice that a neutral unit often won’t attack you until you either attack first or advance into a compound within its territory. However, once you do attack, that lone Cultist will get help from its five friends, who will swoop in and kill your units. You can minimize this by staying in a group and rotating wounded units to the back. Apothecaries can quickly return wounded units to the fight; in dire straits they can even move themselves into danger to heal a hero that might otherwise die. A very Space Marine thing to do, no?

I typically use my early game squad of four Tactical Marines plus a hero or two, and then gradually add in Terminators or Assault Terminators to kill ground units, backed by Devastator Centurions if I need anti-air coverage.

When you have to choose, it’s usually better to finish a slivered (nearly dead) unit, rather than damage a different unit (this may not be true against the AI, however). By destroying the unit, you’ll get experience and morale, and it won’t be able to run off to heal.

The title is dramatic, but the secret is…workflow management. Very dull, but absolutely critical. Because you have only one city, you can only build one thing at a time. Your entire strategy revolves around making sure that you don’t have idle turns where you can’t build the thing you want because you’re out of a resource, or short on population, or building a building you could have avoided with better planning.

Think ahead. The most important currency is time…every building you don’t have to build boosts you in race with the AI. For the economic-minded, it’s all about “opportunity cost.” Examples:

You didn’t prioritize the hero building, so you aren’t earning influence with your Captain. That delays the Icon and the Chaplain, which delays your loyalty production. Worse, maybe you can’t build a Fortress when it’s ready because you’re short on influence; that Fortress might have given a Requisition boost which would have allowed you to build that Relay a turn earlier.You didn’t get around to building a Chaplain, then maybe your loyalty suffers, which makes you waste 3 turns building the loyalty building…and it would’ve been 2 except for the negative loyalty production penalty. You delay building a second Orbital Relay because you need something else and the Relay takes so darn long. But now you’ve just wasted turns…the Relay will pay back its “time cost” in 2 or 3 buildings, and it acts as an influence building, which you can use for an Icon…You built a second hero before buying an Icon. But heroes cost influence, so you’re now make 8 less for lacking the icon, plus another 2-4 for the hero upkeep. Now, maybe you need to waste time building that influence building.

Doc, you’re killing me with all this non-combat stuff!! Yeah, I am. But this is an Impossible Guide. It’s really hard to win with the Space Marines! Even though they are the easiest to learn, their end game units just aren’t strong enough to win without a viciously efficient production machine.

The AI will just churn out units, so you need to be able to counter the numbers as best you can. That means efficient production, and probably overbuilding key units before you encounter your opponents.

I used to stop with two of each unit production building, and then focus on loyalty and population for the rest of the game. Then I thought…why? The extra energy cost to build additional unit producers is negligible at this point, and I’m competing with a hyperproductive AI with six times as many cities as I have. So now I’ll build three or four unit buildings of each type until I can build whatever I want in a single turn. If you’re unsure what to build, put in another loyalty building…that gives a 6% boost to all production (and more if you have outposts to increase your loyalty efficiency).

Three superb technologies…which one do I take? Apothecaries can attach themselves to your advance squad and double their effectiveness by making sure they always fight at full strength. But Stronghold Shielding moves into first place if your Fortresses are under constant threat…the 50% damage reduction finally removes the risk of neutrals wrecking your economy. Finally, Advanced Redoubts can let your city claim distant tiles and potential greatly expand your economy quickly and cheaply.

Extra Infantry Armor isn’t glamorous, but it’s yet another upgrade keeping those Tactical Marines viable into the late game. I have a soft spot for Dreadnoughts which look so cool…they’re also the first tough armored unit with a single model, so they don’t get weaker when wounded.

brings the Vindicator which is a remarkably cheap tank capable of holding the line while you stall to get longer-range infantry units into place. The Thunderfire Cannon is absolutely necessary to clear tiles and heal your armored units, which will become more and more important as the game progresses. Bolter Drill is only useful for units other than Tactical Space Marines, as their accuracy is already maximized by Tactical Doctrine. Do you have any other Bolter-based infantry?

Another tier where you’re spoiled for choice. Lauch Pads should probably be first so you can get your aircraft infrastructure in place to resist the coming storm.

Terminators live up to their name, wiping the floor with any remaining neutrals and absorbing tremendous damage from AI forces. Remember that depleted units are much worse at offense, but just as good at defense, so using a damaged squad to soak incoming fire might be the best use of them.

Multi-Melta weapons turn your Land Speeders and Land Raiders into credible threats, so these are critical if you have those units.

Orbital Deployment changes the game entirely. You were a slow, plodding faction, taking over the map a hex at a time. Now you can drop anybody anywhere anytime.

Co-op note: Because you can’t expand much, your ally is more likely to be the first to trip over the AI. This is a good thing! Orbital Deployment can stop an AI assault cold; your heavily armored units appear instantly to absorb punishing fire while your ally builds up whatever superweapon they’ve been working on. I particularly like Vindicators for this job.

Now we’re bringing the firepower. Devastator Centurions can heavily damage or destroy nearly anything, and at range 3. Assault Terminators are the opposite, mediocre on offense but nearly impervious to physical attacks (but beware T’au Mind War!).

Additional Heavy Bolters gives your Predators and Fortresses some real teeth against ground units who would just shrug off the laser strikes from before. Finally, Fortress Supreme brings an enormous chunk of the map (up to 30 new tiles) to within your city radius. With this upgrade, I’ve had Space Marine cities which encompassed ten outposts, and five or six would be typical. Now your economy should be fine.

Land Raiders aren’t the best, but they’re the best you’ve got, and they really aren’t that expensive. Also, you can load them up and then send them via Orbital Deployment, saving the cost of transport of all the units inside. Well, if you’ve got the Reinforcement Pack, that is.

Defensively, Machine Empathy really helps your mechanical units…even though the regeneration is relatively small, it helps patch up little bits of damage that you accumulate when fighting neutrals or absorbing a random overwatch attack. I keep it active constantly.

The Stormraven Gunship has it all…transport capacity, high health, and good armament. These will be the backbone of your air force.

A little anticlimactic, the ultimate tier contains only one critical element…Aquila Macrocannons. These drop in from space and can secure a battlefield anywhere on the map. They are tough enough to take a lot of damage if you need something to soak up enemy attacks while you ‘reorganize’ your units rearward. Best of luck if you’ve haven’t dropped the cash for the Fortification Pack DLC.

The other technologies are definitely nice to have, but represent incremental improvements. That said, you really shouldn’t engage in an air war until you have Hurricane Bolters on your Stormravens.

Eventually the dreaded moment arrives when you’ve found the enemy. Typically, you’ll spot a weak-looking scout unit and the introductory message will flash up. Tempting as it may be, don’t send your units haring off after the AI. Right behind that lone Guardsman is a huge mass of enemy units ready to surround you, cut off your retreat, and destroy you.

Instead, pull back from the visible range. You now have two or three turns to begin consolidating and preparing for the huge wave of air units which is about to arrive. The T’au are probably the worst, with punishing overwatch, long-range attacks, and strong air units. Fortunately your units are well-balanced and can take a lot of punishment, so you shouldn’t be completely overrun in the first few rounds.

Once those first units show up, you’re probably going to feel pretty overwhelmed. Because of various boosts, the AI units will be much tougher than similar neutrals, and far better at concentrating fire. If you haven’t lost many (or any) units so far in the game, you’re about to get a lesson. Stay grouped up tightly, and don’t be afraid to fall back into a forest or ruin to minimize the AI’s line of sight and prevent ground units from rapidly flanking you…these also give a big boost to ranged damage reduction. Keep heavy units such as Vindicators out front to soak up damage, but cycle them when they get below half health.

Air units are expendable, especially Stormtalons! I usually have a three Launch Pads turning out a new aircraft every 1-2 turns…your Stormtalons will go down almost as quickly. Using Jink (before you move, not after!) means that the AI will expend a lot of attack power to kill air units, and spare the damage to your less agile ground units.

If you’ve built some heavy units, you can weather that first attack. Space Marine units are some of the best on defense, so consider making an orderly retreat back toward your city, buying time to build up a squad of Land Raiders to push back. If you’re farther afield, consider dropping a Macrocannon to anchor your forces, and make liberal use of ruins, forests, and outposts to help your infantry withstand the AI attacks. Bring in waves of troops via Orbital Deployment, and don’t be afraid to drop a Vindicator in some suicidal location just to absorb damage and slow down the enemy. It’s what the Battle Brothers would want, after all…

Wounding air units will send them scurrying away, which isn’t as good as a kill, but at least puts them in the penalty box for a few turns while they heal. The AI is pretty inefficient at healing, so wounded units can clog their supply lines.

By now you’ve organized an armor-based assault with a trailing edge of Devastator Centurions, and you can cautiously plan a few kills. Go for weak units to reduce their morale and make the stronger ones more vulnerable. Don’t forget that most Space Marine vehicles work best in pairs!! Predators and Vindicators are much more effective at damaging the enemy when they are adjacent, and Thunderfires go from mediocre to lethal when paired.

Overconfidence kills! Now’s where it’s easy to make the classic rookie mistakes such as sending that damaged tank forward to chase a wounded unit, or flying in three precious Stormravens to take out a Carnifex, leaving them open to a vicious counterattack. Or worst of all, sending up a bunch of Centurions to be killed, wrecking your anti-air defense.

Usually, the initial probing attacks will develop into a very Warhammer-style static front line, often stretching vast distances….literally dozens of hexes. The AI is excellent at flanking you, and sending groups of units tuned specifically to the weaknesses of your units. Stop any salient from forming, keep whittling away at their army while being very conservative with yours, and eventually the tide will turn.

Finally, you’ll begin to push them back, inch by inch. Now it’s a matter of patience…once you find and kill that first city, the game is (probably) in the bag, and you can either declare a win or push on to destroy the other five or six cities, and get that sweet victory screen.

Here’s my individual breakdown of Space Marine units. My usual mantra that “all units have their place,” and nowhere is that more true than with the Space Marines. I’ll try to give my perspective to assist as you develop your own style. (Note that heroes have their own section above because they are so integral to early game strategy.)

Tactical Space Marines. Have you figured out that I like these guys yet? They are one of the very best units in the game of Gladius. They start off durable and high damage, and only get better as you apply their half-dozen upgrades. Just don’t forget to use Tactical Doctrine, which is both cheap and effective.
I’ve found they don’t quite make it in the endgame, but they are still useful for expanding your map control in neutral territory away from the front lines.

Scouts. Not bad exactly, but hard to justify in the early game when every turn counts. They have the lowest armor of any Marine infantry and only do much damage if they’ve sat still for a turn. I’d say one unit of these could be useful to, well, Scout for enemies in the undergrowth. But I think I’d rather have another Tactical Marine, thank you.

Assault Space Marines. It’s the same story here as with the Scouts. Assault Marines are cool to play with and add mobility. Up close, they pack more punch than Tactical Marines. However, it’s an extra technology to research, and their lack of a range 2 attack limits their usefulness in the overwatch traps I favor in the early game.

Devastator Space Marines. If I need a sniper unit, I start with Devastators. The armor penetration and range are excellent, making them perfect to stand back and shoot Kastelan Robots or Catachan Devils. When using them remember that they only shine when they’ve been in the same hex for a turn…their lascannons are heavy weapons and take a penalty if you move and shoot.
In the later game they can be useful to stand at the edge of a city (or back of an army) and provide a heavy dose of overwatch to adventurous enemy aircraft.

Apothecaries. Absolutely. Totally. My favorite healers in Gladius…adding one unit to a group of Tactical Marines almost eliminates the need to rotate your troops back to heal. Later, you can keep a group behind the lines to act as a field hospital for heroes and heavy infantry. Even better, in co-op they can heal all allied infantry without restriction. Not enough for you? They’re also cheap, costing the same as a Tier 0 Tactical Marine.

Terminators. These infantry are exactly what you need at this point in the game. The Tactical Marines are still holding their own (especially in groups) but are having a hard time pushing into terrain filled with neutral units. Terminators are essentially impossible to one-shot even for the strongest AI units, and can easily beat down any neutrals.

Their Storm Bolters are as good as Tactical Marines at range 1, and better at range 2. Power Fists ensure they can deal with armored enemies. Their health looks a little light at 15 (the same as Tactical Marines) but the Terminator armor effectively makes their health last longer, and makes healing more effective (i.e. 8 points healed is better if those points are more durable.)

Assault Terminators. These units remind me of Aeldari Wraithblades…slow, amazingly resilient (thanks to their Storm Shields’ 67% damage reduction), and useless against air units. I can’t really recommend them over Terminators because of their lack of versatility…the AI will try to hem them in and wear them down with flying units. Even neutral psychneueins can stall them indefinitely.

So, should you use them? I really wanted to try them, so I built a lot and used them in a variety of circumstances. They make great…ablative armor! If you have a valuable unit like a Chaplain, the AI will try to completely surround and destroy him, often committing a dozen units to attack it. Even a nigh-invulnerable unit like the Chaplain will eventually wear down, and they won’t be able to escape because they are surrounded.

However, if you fill a couple of those adjacent hexes with Assault Terminators, you can greatly reduce the Chaplain’s vulnerability and usually leave a path of retreat. Further, the Chaplain can buff and heal the Assault Terminators, which makes them even better as blockers. And if the AI manages to kill one, you can feel confident that he gave his life dearly for the betterment of the Chapter.
Don’t expect too much from them, and you won’t be disappointed. Ahem…as long as you have the Demolition Pack.

Devastator Centurions. Wow! What an infantry unit! Heavily armored and loaded with weaponry, they can wipe out enemy air and take big chunks out of AI superheavies. But they carry heavy weapons, right? Never fear, they have that awesome trait “Slow and Purposeful,” which eliminates the penalties that limit their Devastator cousins.

Despite their high armor, they can be killed fairly easily by a concerted effort. Keep them in the back so they survive to be healed, and remember that their effectiveness drops off rapidly as they lose units. Nevertheless, I’d say these are critical units to a successful strategy.
Oh, what’s that you say? Don’t have the Specialist Pack DLC? Gosh, maybe you’d better stick with the Necrons, my friend.

“Every Space Marine is an infantryman above all…but sometimes it’s good to fire the really big guns.”

Scout Biker. Space Marines on motorcycles with shotguns? The mental image is really cool, but the application isn’t…these are the lowest armored Marine units and are not great at damage, so not worth the time investment to build the Vehicle building.

Razorback. A solid little tank, the Razorback moves 4 hexes which can make your Marines a bit more mobile, and it’s cheap to build; it’s a definite improvement on the Scout Bikers and available at Tier 1. It’s lightly armored so use its bolter array to clean up wounded enemy units rather than leading an assault. Unfortunately, I don’t often have time to research and build these in the early game. And you won’t build it at all without the Assault Pack DLC.

Land Speeder. So…fast. After researching Multi-Meltas, I like these guys; they can essentially go anywhere on the map to help out beleaguered infantry, and the meltas can kill targets that the infantry struggle against. Even in the late game, they can be used as one-shot killers to finish off heavy enemies; don’t expect them to return from the mission, though.
One tip which may prolong their lives: They are amphibious, which can give them a retreat point on watery maps.

Whirlwind. A disappointing support tank. They lack the anti-armor punch of land speeders, they aren’t durable, and their weapon is a true disaster. The Multiple Missile Launcher for some reason has only one attack (?), poor accuracy, and very low damage and armor penetration. Not the best reason to buy the Firepower DLC…I mean, Chaos gets the mighty Brass Scorpion and the Marines get this peashooter? 😊

Hunter. Finally a vehicle I can recommend whole-heartedly. These are your designated anti-air units, and with a range of 3 and excellent armor penetration, they to the job. Keep them in pairs…the accuracy boost makes quite a difference.
I usually put Hunters in the back line and leave them on overwatch. It’s great to see an enemy flyer try to sneak into your back line to wipe out your Apothecaries, only to be turned into wreckage by the Hunter’s Skyspears.

Predator. Do you like tanks? Because the Predator is probably the Gladius gold standard for tanks (competing with the Leman Russ, of course). It’s cheap to build and maintain (3 requisitions per turn), long range, mobile, and benefits from multiple upgrades. Weirdly they start as mostly support vehicles because their lascannons are good for taking out heavy targets at long range (and even better in pairs). Once you add the Additional Heavy Bolters, these tanks can finally lead the charge into massed infantry!

Vindicators. A solid workhorse, I love these guys for defending against a determined AI siege. Their cannons do heavy damage in a single shot, but the Large Blast trait means that they can do respectable damage to infantry groups as well. Once again, you won’t really see them shine until you have two together, which eliminates any ranged damage reduction.

Thunderfire Cannon. Finally, you can clear that wireweed! But seriously, these are one of the most versatile units in the game. Not only can they clear brush, they can heal your armor. I set up a ‘camp’ of Thunderfires behind my lines, ready to repair damaged tanks fresh off the front.
If that wasn’t enough, they have an excellent range 3 attack which can rip through most infantry and severely damage vehicles. There’s a couple of caveats, though. Like with most Space Marine vehicles, you’ll need them in pairs to get the most firepower. Also, despite being ‘vehicles,’ they don’t have the Vehicle trait. This means that their eponymous Cannon (which is Heavy) is much less effective if you’ve moved the unit.
Anyway, keep them out of harm’s way, utilizing their long-range attacks to scare off mobile enemies. They have a couple of solid up-close weapons, but use these at your own risk, as Thunderfires are a juicy treat for the AI (high experience value but low health).

Land Raider. Well, here it is. The ultimate expression of Space Marine vehicle power. And it’s…the best you’ve got! The Land Raider (side note: it’s named after Arkhan Land) isn’t a superheavy, but it is versatile, with a movement of 4 and a relatively low cost. It can also move troops, which is usually best used as an emergency shelter for damaged infantry.

Almost uniquely, these *don’t* work better in pairs. Still, you’ll need a lot of them…when sent as a battalion, you can overwhelm superheavy enemies. But don’t bother until you’ve got the Multi-Melta technology which gives them the cutting power to get through heavy armor at range.

They’ll need a lot of repair, and don’t let them get trapped out front. Their 64 health can’t hold out long against a determined attack. But if you’re careful with your management, a fleet of these can push the center of your attack to victory. Unless of course you don’t have the Reinforcement Pack DLC, in which case, it’s probably not going to go your way…

Stormtalon Gunships. A strictly average aircraft which is probably best for supporting your infantry against persistent neutrals. If you use them in your main combat force, don’t forget to jink *before* you move. You’ll do less damage but it’s worth keeping your Stormtalon alive for another round.

Stormraven Gunship. Now here’s the Space Marine air vehicle we’ve been wanting. It’s tough and versatile, with enough punch to take down some enemies and avoid getting destroyed in a single shot. It’s also a transport, which is a blessing for an infantry-heavy faction with limited mobility (well, after that first orbital insertion).

The Space Marines are unique in many ways, including with this DLC. Unlike all the other add-ons, it only adds units to the Space Marines, and all are themed around a major recent change in the Warhammer Universe. Welcome to the Primaris Marines!

Note that all the Primaris infantry units (and oddly, the vehicles) have 8 armor, so don’t let appearances fool you! They may look like Terminators, but they’re not! 😊

Primaris Intercessors. I have no explanation for this unit, just a few guesses. It’s essentially identical to the baseline Tactical Space Marine, but just slightly worse. With the same cost, same armor, and same abilities, you’ll mostly notice the slight increase in health and armor penetration, and the reduction of sub-units to four (from the original five). This has the effect of producing less damage output from anything dependent on numbers (such as the standard attack).

I rate them slightly worse because the unit isn’t affected by Tactical Doctrine, so it will underperform your Tactical Marines, who will benefit from near-perfect accuracy. Overall, think of Intercessors as a re-skin of the original.

Primaris Aggressors. A pair of bulky brawlers, they can smash anything up close…fists for armored targets, and grenades and flames for groups. Limited by low health, they should be packed in with other units to avoid being cut off…also, don’t let one of the two sub-units die, because that’s an immediate 50% damage reduction. They look great, though.

Primaris Hellblasters. Probably my favorite of the Primaris units, these give you most of the power of the Devastator Space Marines without two of the biggest drawbacks. Although Devastators can fire at range 3, their weapons are heavy, and so not very useful if you’ve had to move before shooting. The Hellblaster plasma rifles don’t have this drawback, and can even be overcharged for a bit more damage, and the armor penetration is even better than the lascannons.
Also, Devastators have absurdly low health for near-immortal transhuman warriors…the Hellblasters have twice as much.

Primaris Inceptors. Just as Hellblasters are a pricier version of Devastators, Inceptors are the costlier big brothers of Assault Marines. Their plasma blasters are good against both armor and groups of units, so they are rarely useless in combat. The jump packs aren’t bad, but I recommend you use them to escape, *not* to enter battle. Huh? Despite their frontline nature, Inceptors don’t have much health and no special damage reduction like Terminators, so they can quickly be overwhelmed. That is, unless they can jump away from danger.

Primaris vehicles don’t have the typical Space Marine mechanized traits which improve them if they are deployed in pairs (e.g. Predators). Simpler, yes, but somehow less…Astartes. (“Come, battle brothers! Let us stand together against this foe!” and such).

Primaris Invader ATVs. I love these things! Not only do they look great roaring around the battlefield, they’re inexpensive and surprisingly well armored for space jeeps. And fast, too, with a five hex movement.

There are a couple of details to understand, though, due to some subtleties with their traits. First, they *aren’t* Open-Topped even though they look like it…this is a good thing defensively. Second, they are technically Bikes, not Vehicles, which means that the Onslaught Gatling Cannon suffers from the movement penalty because it (in turn) has the Heavy trait. In other words, if you park them for a turn they can tear up masses of enemies.

Storm Speeder Thunderstrikes. Another great addition, Thunderstrikes are amphibious skimmers with fantastic mobility. With decent armor and weapons out to range 3, they make a good support unit, particularly given their ability to “mark” targets with their Thunderstrike trait, which makes any target more vulnerable to allies’ attacks. (Yes, it’s true…“you been thunderstruck.” Angus Young should be proud.)

Primaris Redemptor Dreadnought. Although they look a lot like the standard Dreadnought, they play a different role in my opinion. The Dreadnought’s multimelta and powerfist make it ideal for crushing vehicles and single-model units at range one. The Primaris version is more capable of mowing down infantry at range 2 (thanks to all the storm bolters and better accuracy). Also, the touch of damage resistance from Duty Eternal is a welcome assist to durability.

Primaris Repulsor Executioner. This one’s a little hard to evaluate because it piles a ridiculous number of different weapons on a fairly fragile chassis…feels almost Orky that way 😊 This is how I think about it: Consider its range three weapon, the Heavy Laser Destroyer (a remnant of near-omnipotent Neutron Laser Projector that I built into my Cerberus mod unit) in one category, and all the other stuff in another group.

So at long range, the Executioner is a sniper capable of knocking holes in armored units like tanks, providing excellent support and overwatch. Close up, it unleashes a storm of munitions which will kill pretty much anything short of a superheavy.

Why not get up close, then? Well, it’s a bit of a glass cannon. Like apparently all Primaris units, this one’s stuck at 8 armor with no further damage reduction, and it only has 48 health. This is plenty for mopping up neutrals at close range, but will get the tank killed by mid-tier AI units very quickly.

So yes, definitely build these, and use them flexibly….for dangerous heavy enemies, stay at range and use the Laser Destroyer. For lighter units, use the speed and skimmer capabilities to flank the bad guys and then escape to heal. It’s also a transport, so it can rescue beleaguered infantry from the front lines better than almost anything else.

The Space Marines are deceptively simple. Many of the restrictions imposed on the other factions just don’t apply to them, and their units are equally straightforward. And of course, in many ways, the Space Marines are the protagonists of the Warhammer 40K universe. They are the subjects of thousands of pages of writing, and now you can lead them in a glorious crusade across Gladius.

However, I wrote this guide because simple doesn’t mean [/i]easy.[/i]

I hope you’ve enjoyed the guide and learned some things you didn’t know, even if you’re not playing Impossible just yet. Good luck, and please leave comments to help me improve.

***Super Secret Space Marines Strategy*** Time management!! Well, yes, but also: Use Captains to build influence, and use Doctrines early and often.

1) Build your city to focus on research and requisitions; include immediate plans for a Fortress of Redemption on Turn 1. Do not settle for a poor starting location!

2) Research and build infrastructure including an Apothecarion (infantry building), and a Reclusium (hero building.)

3) Build a Captain and another pair of Tactical Space Marines. Expand with your units to capture outposts, generate influence with the Captain, and find sites for future Fortresses.

4) Build fortresses as soon as they are ready. Specialize in requisitions, growth, and/or energy, depending on shortages (but if in doubt, favor energy). Defend your fortresses!!

5) Plan ahead carefully (see Super Secret Strategy above) so that you aren’t stalled by running out of requisitions or population.

6) Move up the tech tree focusing on infrastructure improvements. For units, research Chaplains to avoid needing Company Chapels. Build Tactical Marines and follow research paths to make them stronger rather than trying to research multiple infantry types. From the armory, start with ATVs (or wait for Predators), and eventually work up to Land Raiders and Executioners.

7) Meet the enemy and do not engage initially. With my settings, you should be ready for total war by turn 70-80.

8) Once you have established the enemy’s likely attack path, begin using Orbital Deployment to hinder the advance.

9) Advance to victory by surviving the initial standoff, rotating wounded units, and finally moving steadily forward.

Space Marines make great co-op partners because of their mobility away from their city. Despite the Marines’ bellicose reputation, the game will go better if the AI attacks your ally first, because then you can support them with Orbital Deployment. (You can make this more likely by choosing a starting map which tucks the Space Marines into a corner.) Drop in damage-soaking units like Vindicators and Terminators first (to help bolster the line) and then begin to bring in counterattackers. Don’t be afraid to send a unit to a heroic last stand to disrupt the enemy advance on your ally’s city.

• Negative loyalty is twice as bad as positive loyalty is good (-2% versus +1% per point). Therefore, *stay out of negative loyalty situations.*
• Assume every forest and ruin is full of enemies until you’ve scouted it. Avoid overwatch traps!
• Attack units you can destroy, because this will simultaneously raise your morale and lower theirs. For this reason, carefully consider the order of your attacks to maximize these advantages.
• Move rear-echelon units forward *before* landing the killing blow with a different unit. Any unit within three tiles will gain experience and morale.
• The Jokero trading items can turn a mediocre hero into a near-invulnerable tank. If you don’t know what to buy, non-combat heroes should start with the Tantalising Icon to avoid negative influence. All heroes should consider the Zoat Jerkin, the Adamantium Weave, and Endurance Implant in that order. Fighting heroes should eventually shop for the Dusk Blade, Axe of Blind Fury, and Mourning Blade of Lazaerek. Note that all three of the latter only aid melee attacks.
• Building a lot of good early-game units (such as heroes) is a good substitute for building a few mid-game units, and lets you focus research elsewhere.
• Deploy combined arms. The AI is remarkably good at countering single-unit strategies.