Side with the armies of the Chaos gods of Warhammer 40k, from Renegade Space Marines to Daemon Factions; this is your guide to the dark forces of the warp and beyond.
Updated April 22nd, 2025, by Rob Baer with new information and links to relevant content.
Welcome to the dark side of the Warhammer 40k universe! If you’re trying to learn about the chaotic forces that shape the galaxy, you’ve come to the right place. In Warhammer 40k, Chaos isn’t just a bunch of bad guys; it’s a metaphysical concept, an ever-present corrupting force, and a pervasive religion found all over the galaxy. To the Imperium of Man, it’s known as the Arch-Enemy, and trust us, they’re not exaggerating.
Here is everything you need to know about the Warhammer 40k Chaos Gods, Daemons, and, of course, the Chaos Space Marine Legions.
Dark Gods & Forces of the Warp
Chaos in 40k is as complex as it is terrifying. It’s always lurking beneath the surface, waiting to corrupt, destroy, and reshape everything it touches. Depending on your perspective, Chaos could be the ultimate truth of the 40k universe or its ultimate evil.
Confused? Don’t worry; we’ll break it all down for you. From the dark gods who rule the Warp to the corrupted Space Marines who serve them, we’ll cover everything you need to know about Warhammer 40K’s Chaos forces.
Before we break it down, if you need a broader overview of all the armies in the 40K universe, check out our full guide to Warhammer 40k factions. But if you’re ready to walk on the (very) dark side, let’s get started with the Warp.
The Warp
The Warp is probably the most mind-bending concept in Warhammer 40K lore. Imagine a parallel dimension filled with the raw emotions, psychic energy, and souls of countless beings across the universe. That’s the Warp for you. It’s a hostile, transdimensional realm that’s as essential to the 40K universe as dangerous.
In the grimdark future of Warhammer 40K, faster-than-light travel isn’t about sleek starships zipping through hyperspace. Nope, it’s about tearing a hole in reality and plunging your spaceship into the chaotic maelstrom of the Warp.
Picture flying through a sea of nightmares, and you get the idea. Every time a ship enters the Warp, it’s a gamble. You need a Navigator (a mutant with a third eye to see safe paths), a functioning Gellar Field (an energy shield to keep the nastiness out), and a ton of luck.
The Warp is not just for travel, though. It’s the source of the most nefarious threats in the 40K universe. From this realm come the Chaos Gods and their legions of daemons, the reason for the civil war that split the Imperium and why the Emperor of Mankind is now a withered husk on the Golden Throne. The Warp is pure Chaos, constantly roiling and shifting, and it’s the playground of the four Chaos Gods.
Chaos Gods
Now, let’s talk about the big players in the Warp: the Chaos Gods. The four main gods represent different aspects of Chaos and the darker side of mortal emotions and ambitions. They’re powerful, they’re terrifying, and they’re always at odds with each other.
Khorne: The Blood God
Khorne is all about rage, bloodshed, and honor in battle. He thrives on the fury of combat and the blood of his enemies. His followers are relentless warriors who believe that the more blood they spill, the more favor they gain from Khorne.
Nurgle: The Plague God
Nurgle embodies disease, decay, and the inevitability of death. But he’s also oddly paternal, offering his followers resilience against pain and suffering. His gifts come in the form of plagues and pestilence, and his devotees become living vectors of contagion.
Tzeentch: The Changer of Ways
Tzeentch is the god of change, magic, and ambition. He’s all about plotting and scheming, manipulating fate to achieve his inscrutable goals. His followers are often powerful sorcerers who crave knowledge and power, willing to do whatever it takes.
Slaanesh: The Prince of Pleasure
Slaanesh is the god of excess, pleasure, and indulgence. From hedonistic desires to extreme sensations, Slaanesh embodies the pursuit of gratification at any cost. His followers indulge in every whim and desire, often to their own detriment.
Each of these gods has a unique role in the 40K universe, drawing followers with promises of power, resilience, knowledge, and pleasure. But serving them comes at a steep price. Next, we’ll look at the mortal champions of these gods: the Chaos Space Marines.
Chaos Space Marines
Chaos Space Marines are what happens when the galaxy’s mightiest warriors turn to the dark side. These aren’t just any soldiers; they were once the Emperor’s finest, now twisted and corrupted by Chaos. Their story begins around 10,000 years ago with the Horus Heresy, a galaxy-wide civil war that changed everything.
The Horus Heresy was a cataclysmic event. Horus, the Emperor’s most trusted Primarch, was seduced by Chaos and led a rebellion against his father. Nine of the eighteen Space Marine Legions followed him, including:
- Sons of Horus
- Emperor’s Children
- Iron Warriors
- Night Lords
- Thousand Sons
- World Eaters
- Death Guard
- Word Bearers
- Alpha Legion
The heresy failed, but the traitor legions survived, fleeing into the Eye of Terror, a massive Warp storm. Here, time flows differently, and many of these warriors have been fighting the “Long War” ever since. The Chaos Space Marines are diverse, each legion serving a different Chaos god or pursuing their own twisted goals.
On the battlefield, Chaos Space Marines are fearsome opponents. They combine the skills and technology of their loyalist counterparts with the dark powers of Chaos. Each legion has its own style and specialty, from the World Eaters’ berserk fury to the Thousand Sons’ sorcerous might.
Fielding Chaos Armies
Fielding a Chaos army in Warhammer 40K offers a wide array of strategic options and aesthetic choices. Whether you are drawn to the brutality of Khorne, the pestilence of Nurgle, the trickery of Tzeentch, or the excesses of Slaanesh, there is a Chaos Gods’ faction that will suit your playstyle and hobby interests.
Combining Forces
One of the unique aspects of Chaos armies is the ability to mix and match units from different Chaos factions. This flexibility allows you to create a force tailored to your preferences, combining the best elements of each god’s followers. For example, you could field a core of resilient Plague Marines from the Death Guard, supported by the might of Daemons and the power of Knights.
Painting & Customization
Chaos armies also offer endless possibilities for customization. The corrupted and mutated nature of Chaos units means that no two models need to look alike.
Hobbyists can let their creativity run wild, adding personal touches and unique details to their armies. From rusted and decayed armor to vibrant and otherworldly color schemes, Chaos models are a painter’s dream. Learn about painting your Chaos forces here!
Death Guard
The Death Guard, once known as the XIV Legion, has one of the most tragic and grotesque histories among the Space Marine Legions. Originally led by the grim Primarch Mortarion, they were renowned for their resilience and grim determination on the battlefield.
They were the toughest of the tough, able to endure the most toxic environments and survive where others would fall. Mortarion himself was known for his immunity to poisons and toxins, which he demonstrated by drinking deadly substances with no ill effects.
The Fall to Nurgle
However, their resilience became their curse. During the Horus Heresy, Mortarion and his legion were seduced by Nurgle, the Chaos God of decay and disease. In exchange for their loyalty, Nurgle granted them “gifts” of disease and immortality, transforming the Death Guard into bloated, rotting carriers of pestilence.
Their once-pristine armor became fused with their corrupted flesh, and they became walking vectors of Nurgle’s plagues. On the battlefield, the Death Guard are nearly impossible to kill. Their bodies are riddled with disease, yet they continue to fight, spreading Nurgle’s corruption wherever they go.
Their resilience makes them a formidable opponent, able to withstand immense amounts of damage while slowly advancing toward their enemies. They use this endurance to their advantage, grinding down their foes through sheer attrition.
Units & Tactics
The Death Guard excels in close-quarters combat (not just melee, but they do great in short-ranged firefights as well), where their resilience and tenacity can be fully utilized. Key units include Plague Marines, who are equipped with a variety of deadly, disease-ridden weapons, and Blightlord Terminators, who combine the resilience of Terminator armor with Nurgle’s blessings.
Daemon Engines like the Plagueburst Crawler and Myphitic Blighthauler provide heavy fire support and spread further corruption. Their strategy revolves around slowly advancing and weathering enemy fire, using their durability to outlast their opponents. They also make extensive use of chemical and biological weapons, spreading diseases that weaken and demoralize enemy troops.
If you want to learn how to play the Death Guard in Warhammer 40k, check out our guide on the army here! Or pick up their Combat Patrol Bundle and get hobbying right away!
The Appeal
For hobbyists, the Death Guard offers a unique aesthetic. Their models are grotesque and full of character, with plenty of opportunities for creative painting and customization. From the pus-filled sores and rusted armor to the swarms of flies that accompany them, the Death Guard is a macabre painter’s dream.
Thousand Sons
The Thousand Sons, originally the XV Legion, are known for their tragic history and powerful psychic abilities. Led by the cyclopean Primarch Magnus the Red, they were scholars and sorcerers devoted to the pursuit of knowledge and the mastery of the Warp. Their home world of Prospero was a center of learning and magical study, a paradise for those who sought to unlock the mysteries of the universe.
The Fall to Tzeentch
However, their quest for knowledge led to their downfall. The Thousand Sons’ extensive use of sorcery attracted the attention of Tzeentch, the Chaos God of change, magic, and manipulation.
Despite Magnus’s attempts to protect his legion, their psychic powers spiraled out of control, causing rampant mutations and attracting the ire of the Emperor. The infamous event, the Burning of Prospero, saw their home world destroyed by the Space Wolves, and the Thousand Sons were forced to flee into the Warp.
Desperate, they pledged themselves to Tzeentch, who offered them stability in exchange for their loyalty. Magnus was transformed into a Daemon Primarch, and his legion became the chosen sorcerers of Tzeentch.
However, this pact came with a curse. Many of the Thousand Sons were turned into mindless Rubric Marines, their bodies reduced to dust and their souls trapped in their armor, forever bound to their sorcerer leaders.
Units & Tactics
The Thousand Sons are a psychic powerhouse on the battlefield. Their armies are led by powerful sorcerers, including Magnus himself, and units like Rubric Marines and Scarab Occult Terminators support them. They also summon daemonic allies to bolster their forces and bring more magical firepower to the table.
Their strategy revolves around the use of psychic powers to control the battlefield, disrupt enemy plans, and unleash devastating attacks. They rely on their sorcery to outmaneuver and overpower their enemies, making them one of the most unique and challenging armies to play.
If you want to learn how to play the Thousand Sons in Warhammer 40k, check out our guide on the army here! Or pick up their Combat Patrol Bundle and get hobbying right away!
The Appeal
For collectors and painters, the Thousand Sons offer an eye-catching aesthetic with their ancient Egyptian-inspired armor and arcane symbols. Their models are rich in detail, with plenty of opportunities for creative painting and customization. The blend of magic, tragedy, and power makes the Thousand Sons a compelling choice for those who enjoy the darker, more mystical aspects of the Warhammer 40K universe.
The World Eaters
If you’re diving into the chaos-infested world of Warhammer 40K, the World Eaters are a faction you won’t want to miss. These guys are the epitome of brutality, rage, and unrelenting combat, driven by their devotion to Khorne, the Chaos God of Blood and Skulls. Let’s look closer at their origins, connections to Khorne, tactics, and units that make them one of the most feared forces in the galaxy.
Origins of the World Eaters
The World Eaters started as the XII Legion of the Space Marines, led by their Primarch, Angron. Unlike other Primarchs, Angron’s story is particularly tragic and bloody. He was discovered on the brutal planet of Nuceria, where he was enslaved and forced to fight in gladiatorial arenas. This experience shaped Angron into a ruthless warrior, and his hatred for his captors and the Emperor, who later found him, never truly faded.
Angron’s influence on his Legion was profound. He introduced the “Butcher’s Nails,” a cybernetic implant that drove the warriors into uncontrollable fits of rage, perfect for close-quarters combat but at the cost of their sanity. Under Angron’s command, the World Eaters became known for their savage fighting style and lack of discipline, preferring to engage in melee combat rather than strategizing from afar.
Devotion to Khorne
The World Eaters’ shift from loyal Space Marines to Chaos devotees was almost inevitable, given their nature. Khorne, the Chaos God of Blood and Skulls, values strength, martial prowess, and the shedding of blood above all else. The World Eaters, with their bloodthirsty and brutal approach to warfare, were a perfect fit.
Their allegiance to Khorne was solidified during the Horus Heresy, a galaxy-spanning civil war that saw many Space Marine Legions turn against the Emperor. The World Eaters embraced Khorne’s creed wholeheartedly, becoming berserkers who fought not just to win battles but to offer as many skulls as possible to their god. This transformation only intensified their savagery and marked their complete fall from grace.
Tactics & Units
When it comes to tactics, the World Eaters are straightforward: get in close, hit hard, and don’t stop until everything is dead. They favor direct assaults and brutal close-combat engagements; eschewing ranged weapons and subtlety for the sheer joy of melee carnage.
Key Units:
- Khorne Berzerkers: The backbone of any World Eaters army, these are elite warriors completely consumed by rage. Armed with chainaxes and pistols, they rush into battle with a singular purpose: to kill in Khorne’s name.
- Blood Slaughterers: These daemon engines are an embodiment of Khorne’s fury, designed to charge into enemy lines and wreak havoc with their deadly claws and weapons.
- Skulltaker: A renowned daemon of Khorne, often included in World Eaters forces, who specializes in decapitating enemy leaders and adding their skulls to Khorne’s throne.
- Chaos Lord: Leading the charge, these commanders are fearsome in their own right, often equipped with the Butcher’s Nails and dedicated to leading their troops in the front lines.
If you want to learn how to play the World Eaters in Warhammer 40k, check out our guide on the army here! Or pick up their Combat Patrol Bundle and get hobbying right away!
The Appeal
The World Eaters exemplify raw, unrestrained aggression in the Warhammer 40K universe. They’re the go-to faction if you’re looking for a force that thrives on close combat and embodies the chaotic fury of Khorne. Whether you’re a newcomer or a seasoned player, the World Eaters offer a rich, brutal, and exhilarating experience on the tabletop.
Chaos Knights
Chaos Knights are the towering, fearsome war machines that have fallen under the sway of the Chaos gods. These once-loyal Imperial Knights have turned their backs on the Emperor, embracing the dark powers of the Warp. Standing tall and imposing, they embody destruction and corruption, wreaking havoc wherever they tread.
Origin & Background
The origins of Chaos Knights trace back to the Horus Heresy, where some Knight households sided with Horus and the forces of Chaos. These knights were drawn into the Eye of Terror, where they became twisted and corrupted by the Warp. Over millennia, many other knightly houses have succumbed to the allure of Chaos, abandoning their oaths to the Emperor in exchange for power and immortality.
Chaos Knights are adorned with grisly trophies, spikes, and chains, their once-noble forms now twisted into nightmarish engines of war. Each Chaos Knight reflects the dark god it serves, whether it’s Khorne’s blood-soaked rage, Nurgle’s pestilent decay, the arcane mutations of Tzeentch, or the hedonistic excess of Slaanesh.
Key Characteristics
Chaos Knights are massive war machines, towering over the battlefield and with devastating weaponry. They boast thick armor, advanced shielding, and a variety of deadly armaments. From giant chainswords and thunderstrike gauntlets to thermal cannons and gatling guns, these behemoths can annihilate infantry, vehicles, and even other Titans.
Each Chaos Knight is a force to be reckoned with, capable of single-handedly turning the tide of battle. Their presence on the battlefield is a psychological weapon as much as a physical one, instilling fear and dread in their enemies.
Tactics & Units
Chaos Knights can be fielded as a standalone army or as part of a larger Chaos force. They excel in head-on assaults, using their size and firepower to break enemy lines and crush opposition. Key units include the Despoiler, Desecrator, and Rampager, each with a specialized role and weapon loadout.
The Despoiler is a versatile knight, capable of both long-range fire support and close combat devastation. The Desecrator excels in taking down enemy Titans and other large targets, while the Rampager is a close-combat monster, ripping through enemy ranks with its melee weapons.
If you want to learn how to play the Chaos Knights in Warhammer 40k, check out our guide on the army here! Or check out their most recent Battleforce here to stay hobbying right away!
The Appeal
For hobbyists, Chaos Knights offers a unique challenge and an opportunity for impressive customizations. Their large, detailed models provide a canvas for elaborate paint schemes and conversions. The combination of their imposing size and intricate details makes them a centerpiece for any Chaos army.
Chaos Daemons
Chaos Daemons are the horrifying entities that inhabit the Warp, serving the will of the Chaos gods. These creatures are manifestations of the dark gods’ powers and desires, each one a twisted reflection of the god it serves. From the brutal bloodlust of Khorne’s minions to the pestilent abominations of Nurgle, Chaos Daemons are a force of pure malevolence.
Role of Daemons in Chaos
Daemons are the foot soldiers of the Chaos gods, summoned into the material universe to wreak havoc and spread corruption. They are born from the Warp’s raw emotions and psychic energy, taking on forms that embody the essence of their patron gods. When the veil between reality and the Warp is thin, daemons can break through and manifest in real space, bringing destruction and chaos.
Khorne Daemons
Khorne’s daemons are brutal, bloodthirsty warriors driven by an insatiable desire for violence and carnage. From the fearsome Bloodletters to the colossal Bloodthirsters, these daemons are relentless in their pursuit of skulls for the Skull Throne. Their tactics are straightforward: charge into battle, hack, slash, and spill as much blood as possible.
Slaanesh Daemons
Slaanesh’s daemons are seductive and deadly, blending beauty with horror. The lithe and graceful Daemonettes dance across the battlefield, their claws slicing through enemies with lethal precision. Slaanesh’s Greater Daemons, the Keepers of Secrets, are terrifying in their allure, combining swift agility with devastating power. These daemons revel in excess and sensation, seeking to overwhelm their enemies!
Tzeentch Daemons
Tzeentch’s daemons are embodiments of change, magic, and deception. These daemons are often bird-like in appearance, reflecting their master’s affinity for transformation and manipulation. Key units include the Horrors, which come in pink and blue varieties. Pink Horrors can cast powerful spells, while Blue Horrors split into smaller Brimstone Horrors when destroyed, making them a frustratingly resilient unit.
The Lords of Change, Tzeentch’s Greater Daemons, are formidable sorcerers capable of reshaping reality with their arcane powers. These daemons thrive on unpredictability and chaos, using their magical abilities to outmaneuver and confound their enemies. On the battlefield, Tzeentch’s daemons rely heavily on their psychic prowess, casting devastating spells to control the flow of combat.
Nurgle Daemons
Nurgle’s daemons are the most repulsive and resilient of the Chaos entities. They embody disease, decay, and the inevitability of death. Plaguebearers, the rank-and-file soldiers of Nurgle, are resilient and tough, capable of withstanding significant damage while spreading Nurgle’s contagions. The Beasts of Nurgle, though appearing jovial and friendly, are lethal in combat, spreading diseases with their every move.
The Great Unclean Ones, Nurgle’s Greater Daemons, are massive, bloated creatures of filth and pestilence. They are tough to kill and can heal themselves and their allies, making them a significant threat on the battlefield. Nurgle’s forces often rely on attrition, slowly wearing down their enemies through sheer durability and the relentless spread of disease.
If you’re ready to unleash the raw power of the Warp, check out our Chaos Daemons guide for all the lore, strategies, and rules you’ll need. Or pick up their Combat Patrol Bundle and get hobbying right away!
Emperor’s Children
Origin & Background
The Emperor’s Children are the ultimate divas of Chaos Space Marines. Once the Emperor’s favorite perfectionists, these prima donnas fell hard for Slaanesh, the Chaos God of excess and sensory overload.
Led by their fabulous Primarch, Fulgrim, they’ve traded honor and loyalty for endless debauchery and ear-splitting sonic weapons. If you like your battles loud, flashy, and downright unhinged, this is your jam.
Key Characteristics
The Emperor’s Children started as obsessive perfectionists, achieving glory and honor as the III Legion. But their Primarch, Fulgrim, took the whole “pursuit of excellence” thing a bit too far and wound up making a deal with Slaanesh. Now, they’re Chaos’s most flamboyant warriors, rocking out with sonic weaponry that turns combat into a heavy metal concert of destruction.
The Appeal
These guys thrive on high-risk, high-reward gameplay, specializing in perfectly executed attacks that leave enemies dazzled (or dead). With their Noise Marines and flair for sensory overload, Emperor’s Children bring a uniquely chaotic flavor to 40k.
Think you can handle their symphony of destruction? Check out our Emperor’s Children guide for all the rules, lore, and tips to play like a true rock god. Or pick up their Combat Patrol Bundle and get hobbying right away!
Frequently Asked Questions About Chaos in Warhammer 40k
What is the Most Powerful Chaos God in Warhammer 40K?
Each Chaos god has its own strengths and areas of influence, making it difficult to determine a single “most powerful” god. It often depends on the context and the specific battles or campaigns.
Can Chaos Space Marines Ally With Chaos Daemons?
Yes, Chaos Space Marines can ally with Chaos Daemons, creating versatile and powerful armies that combine the strengths of both factions.
Are Chaos Knights Good For Beginners?
Chaos Knights can be a good choice for beginners due to their relatively low model count and straightforward playstyle, though they require careful positioning and strategic planning.
What is the Main Weakness of Nurgle’s Forces?
Nurgle’s forces are typically slow-moving, making them vulnerable to long-range attacks and fast-moving enemies that can outmaneuver them.
How Do You Counter a Psychic-Heavy Thousand Sons Army?
To counter a Thousand Sons army, consider fielding units with strong psychic defenses and taking out their most powerful psykers first!
Final Thoughts on Warhammer 40k Chaos Gods & Factions
Chaos in Warhammer 40k is a multifaceted and deeply engaging aspect of the lore and the game. Whether you are a newcomer looking to start your first Chaos army or a seasoned player seeking to expand your forces, the Dark Gods offer endless opportunities for both gameplay and hobby enjoyment.
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Which of these Gods of Chaos, Warhammer, and factions will you play in 40k?
