Warhammer 40K Space Marines: how are they made?

Space Marines are the ultimate defenders of humanity in Games Workshop's Warhammer 40,000 (1987). They're legendary warriors bound by duty, honor and sometimes a touch of madness. They look like demigods, but they're still very much human. Their origins, their chapter houses and the dark paths some of them tread show just how deep their lore goes.

To me, they're the ultimate result of humanity's quest to take on the looming threat of chaos. In other words, "they're basically the superheroes we need in this wild Universe."

Space Marines look invincible, but they're still human underneath the power armor

Picture yourself as an average person living in the Imperium, and here come the Space Marines. They're massive, intimidating figures in power armor, and you hardly ever see them without it. When they do talk, it's sealed up inside their suits, chatting away on their vox units. To regular people, that sounds like a bunch of radio clicks.

At first you might think they're silent statues standing around. But the moment they unleash their firepower, or a giant fist comes smashing down, you realize you're in for a world of hurt. As tough and invincible as they look, though, they can mess up like the rest of us, and they've got their vulnerabilities.

They weren't always super soldiers. They started out as regular humans and went through intense processes to become living weapons: genetic upgrades, cybernetic enhancements and training so brutal it's practically a rite of passage. Those who make it through come out looking like demigods, but they've got their own battles to fight. Thanks to science from the Emperor of Mankind, most of which has sadly been lost in the sands of time, these select few live far longer than an average person and fight like champions, decked out in high tech armor and armed with the most powerful weapons around.

The Thunder Warriors were the first Space Marines of the Unification Wars

Once upon a time, the forerunners of Space Marines were known as Thunder Warriors. The Emperor of Mankind created them to bring everyone together on Terra during the Unification Wars, around the tail end of the 29th and the 30th Millennium. In that chaotic period of endless brawls, the feuding factions of Earth were finally put in their place by the Emperor and these unstoppable ironclad legions. A legendary showdown ended with everyone uniting under one banner.

These original genetic creations weren't as long lived as the Space Marines we know now. They had a wild streak, both mentally and physically, and they were definitely stronger than their Astartes successors. They played a huge role in shaping what we now call the Imperium of Man.

Because of their genetic quirks, however, they were seen as a liability after the war. Following the Emperor's orders, the Legio Custodes quietly took them out behind the scenes. To keep things tight, history got a makeover, claiming they all went down in the last epic battle of Terra. It's a plot twist I didn't see coming, but I'm not mad about it.

The Primarchs and the 20 Space Marine Legions

After a lot of trial and error and decades of hard work, the Emperor finally nailed down the perfect recipe for creating Astartes. This led to the birth of the mighty Primarchs and the formation of 20 Space Marine Legions.

The grand plan was for these top tier Astartes to lead their own chapter houses on some seriously ambitious crusades. Then the Chaos Gods crashed that party, and things took a wild turn.

How Space Marine recruits are chosen across the galaxy

Not many make it through the process of becoming a Space Marine. But with a galaxy this huge and plenty of potential aspirants to choose from, the odds even themselves out. It's definitely not a walk in the park, but when you dangle the chance of becoming a demigod in front of someone, it's no wonder they're willing to dive into that meat grinder.

The application process is a mixed bag depending on the planet you're from, but one thing's for sure: they only scoop up the cream of the crop. Some people apply at the chapter house, while others endure a tough selection process that weeds out all but the strongest contenders. Some are even kidnapped, and there are tales of potential recruits being scouted right from birth.

On planets with more of a tribal feel, the toughest warriors are handpicked from their tribes, pulling off impressive feats to prove they've got what it takes. Then comes the physical challenge: long, intense and painful augmentation surgeries that put their bodies to the test. For those who survive, it's worth it, because they gain a whole range of benefits and abilities that make them superhuman.

The 19 gene seed organs that turn a human into an Astartes

Those new abilities come from something called gene seed. Think of it as a mix of genetic material packed with special cells, unique organs and viral machines, implanted into a willing teenage human to transform them into an Astartes. There are 19 different types, each with its own special role and its own unusual name.

• A second heart, which boosts the oxygen and nutrient supply and helps injured Astartes stay alive until help arrives.
• The Ossmodula, which secretes growth hormones and fuses the ribs into a protective plate.
• The Biscopea, which enhances physical strength by promoting muscle growth.
• The Haemastamen, which changes blood composition for better oxygen transport.
• Larraman's Organ, which quickly forms clots and scar tissue around wounds.
• The Catalepsean Node, which lets Astartes function without sleep, though it can lead to psychosis.
• The Preomnor, which allows digestion of otherwise harmful substances.
• The Omophagea, which lets Astartes recall memories from creatures they consume.
• The Multi-lung, a third lung that boosts oxygen intake and filters toxins.
• The Occulobe, which improves vision in low light.
• Lyman's Ear, which replaces the ear, preventing dizziness and amplifying and filtering sound.
• The Sus-an Membrane, which enables prolonged hibernation for survival after severe injuries.
• The Melanchrome, which regulates skin melanin in response to sunlight.
• The Oolitic Kidney, which detoxifies the body in emergencies.
• The Neuroglottis, which tests substance toxicity and aids in scent tracking.
• The Mucranoid, which seals the skin for protection during suspended animation.
• Betcher's Gland, which produces a blinding acid for offense.
• The Progenoid Glands, which prevent DNA rejection and allow gene seed to be harvested.
• The Black Carapace, which connects directly to the cybernetic systems of power armor.

Why new gene seed is so hard to come by

Getting new gene seed is tricky, because humanity has long lost the knowhow to make more. On top of that, those implanted with tainted gene cultures often end up dealing with serious mutations and flaws. It's a tough gig.

The Thousand Sons struggled badly with wild mutations, and they eventually fixed it in a dramatic way that involved their entire chapter. Meanwhile, a chapter's Apothecary goes into full treasure hunter mode to harvest the precious gene seed, which makes it a high stakes game of tag.

Primaris Marines and Belisarius Cawl's three extra organs

Originally, there were just two ways a Space Marine's journey could end: a glorious death on some distant world, or being entombed in a Dreadnought and turned into a walking tank. With the arrival of the 41st Millennium, a new option appeared thanks to Archmagos Dominus Belisarius Cawl. By gathering samples from the gene seed of the 20 Primarchs, he figured out how to elevate regular Astartes into Primaris Marines.

Becoming a Primaris is a rare and challenging feat, but those who make it are not only highly respected, they're also nearly unstoppable in battle. With just a 0.001% chance of genetic quirks, they've dodged the issues other chapter houses face. Primaris Marines come with all the original gene seed upgrades plus three extra enhancements.

Sinew Coils are strong coiled cables placed in the muscles, boosting a Primaris Marine's strength so much that they can crush a skull with one hand, bite through metal cables and punch through hardened flak armor like it's paper. The Magnificat is a tiny lobe in the cortex, known as the amplifier, that boosts other gene seed abilities, resulting in bigger size and muscle mass. Then there's the Belisarian Furnace, a dormant organ that kicks in during severe injury or stress, releasing a powerful mix that cauterizes wounds and rapidly regrows bone tissue and muscle, helping them survive even the toughest injuries.

Space Marine weapons, and why the bolter stands out

These towering titans are loaded with all kinds of deadly weapons to take down heretical and xeno hordes. For ranged attacks, they've got powerful artillery and orbital bombardments. Their arsenal includes promethium spewing flamers, bolters, heavy stubbers and plasma guns.

Even an unarmed Space Marine is like a martial arts expert, with lightning fast reflexes and enough strength to snap the necks of most xenos with one hand. If they have psychic powers or cybernetic upgrades, forget it. A Space Marine is a relentless force that won't back down until it's taken out, fully restrained or blown to bits.

You can't talk about Space Marines without the bolter. It's a staple of the 40K universe, a fan favorite firearm and definitely one of the coolest weapons ever invented. Bolters come in all sorts of variants, like the hefty dual barrel bolter, the spear mounted Guardian Spear used by the Adeptus Custodes, and a smaller pistol version. With a satisfying kachunk, they fire .75 caliber rounds that are rocket powered and explosive tipped. One bolter round can blow someone in half or completely detonate them if it hits the right spot, and they're perfect for taking down bigger beasts.

Power armor and the Space Marines' vehicles

The thing that makes Space Marines look cool, intimidating and sometimes maybe a bit silly is their power armor. It acts like a fortress, keeping them safe from threats on the battlefield. The armor can connect with all sorts of tech, and it's completely sealed to protect the wearer from extreme temperatures, harsh environments, radiation, toxins and even the cold vacuum of space. Locked away in those suits, Space Marines are practically unstoppable.

Big soldiers need hefty rides, and their garages are packed with armored APCs, gravity defying Land Speeders, giant motorcycles and larger than life tanks. It's a cool collection of mechanized hardware. They also have their signature Thunderhawk drop ships, portable jump packs and system spanning fleets of strike cruisers and attack vessels "that are more heavily armed floating Cathedrals than Starships." When Space Marines roll out for a fight, they bring their biggest guns.

Space Marine chapter houses each have their own flavor

The term Space Marine isn't one size fits all. Astartes aren't one big group fighting for the same cause. They're split into many unique chapter houses, each with its own flavor, often based on the Primarch who founded them, so no two chapters are alike.

The Imperial Fists are the galaxy's red shirts, diving headfirst into every battle. On the flip side, the Night Lords are all about stealth, lurking in the shadows with their secretive goals. The Ultramarines pretty much do their own thing as long as they're stopping chaos, and the White Scars are all about their own agenda. Chapter houses rarely meet or team up except during big crusades. Most of the time, they're focused on their own missions, the threats that come their way and the worlds they protect.

Space Marine beliefs and their view of ordinary humans

Space Marines have a quirky belief system. Some chapter houses have their own unique doctrines based on their home worlds, but almost all Marines have pledged their loyalty to the God Emperor who created them or the Primarch who leads them. Thanks to their strict training, they become the defenders of humanity, protecting it from the dangers of deep space and even from itself.

Yet many of them, and even some entire chapters, don't have a warm view of regular humans. They often see them as weak and fragile, and as obstacles in their mission to wipe out the enemies of the Imperium. The twisted idea of acting for a so called greater good leads them to commit questionable and sometimes awful acts in the name of keeping order, including wiping out entire populations or destroying whole planets if there's even a hint of xeno or chaos lurking around.

How Space Marines fall to become Chaos Space Marines

Even though they look like unbeatable immortal superhumans, Space Marines can fall to corruption like anyone else. It usually takes more time and effort to push them over the edge, but when it happens, an Astartes transforms into a Chaos Space Marine.

These twisted creatures are walking nightmares: psychotic, genocidal murderers decked out with creepy gifts from their dark patrons. They pursue their own sinister goals or chase favor from their chosen Chaos God, and many dream of shedding their humanity through apotheosis to become immortal Daemon Princes.

Chaos Space Marines come in all shapes, sizes and colors of armor, depending on which Chaos God or fallen Primarch they follow, and even more subgroups and smaller factions splinter off from there. It's an endless wave of chaos, and if they were ever united as one, they could put the galaxy or even the whole universe at serious risk. From the power armor to the darker paths some of them tread, the lore surrounding these warriors is as deep as the galaxy itself.