Chaos Space Marines – Warhammer 40k Guide

The Chaos Space Marines were once defenders of the Imperium. Now they are traitors who have turned their backs on the Emperor and sworn themselves to the Dark Gods of Chaos in exchange for power. For ten thousand years they have waged the Long War against the Imperium and anyone else who stands in their way.

This guide covers who they are, how the army plays in Warhammer 40,000 11th Edition, which models to start with, and how to paint them.

Who Are the Chaos Space Marines?

The Chaos Space Marines were once loyal Astartes, the Space Marines who were the Emperor’s finest soldiers, before they were seduced by Chaos. Many turned during the Horus Heresy, and others have fallen in the ten millennia since, as renegade Chapters and warbands broke away from the Imperium.

They serve the Chaos Gods, Khorne, Tzeentch, Nurgle and Slaanesh, either individually or as Chaos Undivided. Led by warlords such as Abaddon the Despoiler and countless lesser Chaos Lords, they fight alongside cultists, mutants, daemon engines and daemons in an endless campaign of terror.

The Chaos Space Marines army covers the Traitor Legions and warbands such as the Black Legion, Word Bearers, Iron Warriors, Night Lords and Alpha Legion, plus renegades like the Red Corsairs. The god-devoted Legions such as the Death Guard have their own armies on the tabletop. Their ranks include Possessed, whose bodies host daemons, as well as Chosen, Terminators and jump-pack Raptors.

What Are the Chaos Space Marines Army Strengths?

Chaos Space Marines are a flexible, aggressive army. They can field solid power-armoured infantry, elite melee units, heavy weapon teams and daemon engines, and they reward players who like to take risks.

Key strengths include:

• Versatile units: Havocs bring heavy firepower, while Chosen, Possessed and Terminators hit hard in melee. You can lean towards either or mix both.
• Risk and reward: In recent codexes the army rule has been built around Dark Pacts, which let units power up their attacks at the risk of damaging themselves. Check your current codex for the exact wording.
• Daemon engines and Warp power: Forgefiends, Maulerfiends, Possessed, Daemon Princes and sorcerers give the army a supernatural edge that loyalist Marines don’t have.

However, they do have some limitations:

• Elite and expensive: Terminators, daemon engines and big characters are powerful but cost a lot of points, so you’ll often be outnumbered.
• Risky by design: Pushing your luck with the army’s abilities can backfire and cost you models at the worst moment.

For army building, 11th Edition’s Detachment Points system lets you combine detachments, and your existing Chaos Space Marines codex stays valid until the faction’s 11th Edition codex arrives. See 11th Edition rules changes for how that works, and check the Munitorum Field Manual for current points.

Where Do Beginners Start?

Here are some essential models for new players, along with reasons why each is useful:

• Chaos Space Marines / Legionaries: The backbone of your army, these power-armoured warriors are effective in both shooting and melee and can take on most battlefield jobs.
• Havocs: Armed with heavy weapons, Havocs provide ranged firepower for dealing with vehicles or large units from a distance.
• Chaos Lord: A capable fighter who leads a squad into battle and makes it more dangerous.
• Daemon Prince: A big, terrifying centrepiece model and a strong melee threat.
• Chaos Land Raider: A heavily armoured transport for delivering elite units such as Chosen or Terminators into combat, with plenty of firepower of its own.

Starting with these models gives you a solid foundation to explore different strategies with. The Chaos Space Marines Combat Patrol covers several of them in one box.

How To Paint Chaos Space Marines

Difficulty: Beginner to Intermediate

Painting Chaos Space Marines gives you huge creative freedom. With several Traitor Legions and countless renegade warbands, almost any colour scheme can work. Here are three straightforward Citadel recipes, plus the classic Legion schemes.

Colour Schemes

Red warband (Word Bearers style)

• Base colour: Khorne Red for the armour.
• Shading: Nuln Oil or Agrax Earthshade to deepen the recesses.
• Highlights: Evil Sunz Scarlet on the edges.
• Accent colours: A brass such as Brass Scorpion for trim, Leadbelcher for weapons and chains.

Green renegade warband

• Base colour: Caliban Green for the armour.
• Shading: Coelia Greenshade or Nuln Oil in the recesses.
• Highlights: Warpstone Glow, then a fine edge of Moot Green.
• Accent colours: Leadbelcher for metal details, and a purple such as Naggaroth Night for cloaks or decorative elements.

Bone and black

• Base colour: Zandri Dust for the armour.
• Shading: Agrax Earthshade for depth.
• Highlights: Ushabti Bone on raised areas.
• Accent colours: Black for details and weapons, with Khorne Red for eye lenses and symbols.

Legion schemes: For the Black Legion, use Abaddon Black (armour), Retributor Armour (trim), Leadbelcher (metallics), Mephiston Red (eye lenses) and Nuln Oil (shading). For the Word Bearers, use Khorne Red, Leadbelcher and Agrax Earthshade. The Black Legion’s black and gold is the most iconic scheme and is surprisingly forgiving.

Painting Techniques

• Undercoat: Start with an even coat of spray primer such as Chaos Black or Leadbelcher to suit your chosen scheme.
• Washing: Use washes like Agrax Earthshade or Nuln Oil to darken armour recesses and add depth. This also gives a gritty, worn look.
• Drybrushing: Drybrush textured areas, armour trim and chains. A light pass of Dawnstone or Stormhost Silver works well for worn metal.
• Edge highlighting: Use a fine detail brush and a lighter shade to pick out the edges of armour plates and weapons.
• Corruption effects: Technical paints like Nurgle’s Rot, Typhus Corrosion, Blood for the Blood God and Nihilakh Oxide add quick, convincing grime, gore and corrosion.

What makes Chaos Space Marines especially fun to paint is the corruption detail: trophy racks, daemonic mutations and Chaos iconography all give you chances to personalise models, and weathering like chipped paint, rust and grime is forgiving to apply. For a full step-by-step, see our Chaos Space Marines painting guide.

Chaos Space Marines Lore and History

The Chaos Space Marines are the dark reflection of the Imperium’s greatest warriors: Space Marines who turned against the Emperor of Mankind during the galaxy-spanning civil war known as the Horus Heresy. Ten thousand years ago, nine of the eighteen Space Marine Legions followed Warmaster Horus in his rebellion, plunging the Imperium into the most devastating conflict in its history.

The nine Traitor Legions were the Sons of Horus (later the Black Legion), the Word Bearers, Iron Warriors, Night Lords, Alpha Legion, Emperor’s Children, World Eaters, Death Guard and Thousand Sons. After their defeat at the Siege of Terra and the Scouring that followed, most fled into the Eye of Terror. Time flows strangely in this vast Warp storm, and many traitors who fought in the Heresy still wage war today.

The most powerful Chaos Space Marine force is Abaddon the Despoiler’s Black Legion, which has launched thirteen Black Crusades from the Eye of Terror. The Thirteenth finally brought down the fortress world of Cadia, and the Great Rift that tore the galaxy in two opened in the turmoil that followed. It was the greatest Chaos victory since the Heresy itself.

The gods reward their champions with gifts and Marks of Chaos. The most favoured ascend to become Daemon Princes, while the failures devolve into mindless Chaos Spawn. The warbands range from disciplined military forces like the Iron Warriors to frenzied cult armies, each shaped by millennia of war.

Chaos Space Marines in the Current Meta

Chaos Space Marines have a deep roster and several detachments to choose from, so you can build very different armies around daemon engines, elite infantry or characters. With 11th Edition’s Detachment Points system, you can also mix smaller detachments rather than picking just one.

Competitive builds shift with every balance update, so we don’t list a single “best” build here. Common themes have included daemon-engine-heavy lists using Forgefiends and Maulerfiends, and elite infantry lists built around Chosen, Possessed and Terminators. The Dark Pacts mechanic adds a risk-reward element that skilled players can exploit.

That flexibility is a strength and a challenge: list building has a steep learning curve, but the army can adapt to a shifting meta. The Daemon Prince remains a popular centrepiece. For the latest competitive picture, see our faction tier list.

Collecting Chaos Space Marines

Chaos Space Marines offer one of the deepest collecting experiences in Warhammer 40,000, with a huge range of infantry, daemon engines and special characters. Models span decades of design, so you’re free to mix modern sculpts with classic conversions.

Begin your collection with the Chaos Space Marines Combat Patrol, which gives you a core of Legionaries and characters. From there, expand with a box of Chosen (elite infantry), a Forgefiend or Maulerfiend (daemon engine), and characters like a Daemon Prince or Dark Apostle. The Legionaries kit is very versatile, with lots of weapon options and Chaos accessories.

If one Traitor Legion appeals to you, build your army around its look and playstyle. The Black Legion is the most flexible choice, while the Word Bearers, Night Lords and Iron Warriors each have a distinct visual identity. Many players also enjoy converting their models, adding spikes, trophies and mutations from the extensive Chaos range. Visit our CSM painting guide for scheme ideas.

Related Armies

If you enjoy Chaos Space Marines, you might also like these armies:

• Death Guard — The Death Guard are a Traitor Legion devoted to Nurgle’s plagues.
• Thousand Sons — The Thousand Sons bring powerful sorcery as Tzeentch’s Traitor Legion.
• World Eaters — The World Eaters, Khorne’s Legion, are the most brutal melee-focused Chaos Space Marine army, home of the Khorne Berzerkers.
• Chaos Daemons — The daemons of the Warp, natural allies of the Traitor Legions.

Frequently Asked Questions

Who are the Chaos Space Marines?

Chaos Space Marines are Space Marines who have turned traitor and sworn allegiance to the Chaos Gods, many during the Horus Heresy and others since. For ten millennia they have waged the Long War against the Imperium from the Eye of Terror and other Warp-tainted regions.

Are Chaos Space Marines good for beginners?

Chaos Space Marines are a solid beginner choice. They play similarly to loyalist Space Marines but with a more aggressive, melee-oriented twist. Their range of units is diverse, and their dark aesthetic appeals to many new players.

What are the strengths of Chaos Space Marines?

Chaos Space Marines combine the toughness and versatility of power-armoured infantry with daemon engines, Possessed, Daemon Princes and hard-hitting melee units like Chosen. Their Dark Pacts mechanic lets you push units harder at a risk.

What are the weaknesses of Chaos Space Marines?

Their elite units are expensive, so they’re often outnumbered, and they lack loyalist-only technology such as Primaris units. Dark Pacts can backfire, and leaning on a few big daemon engines or characters makes an army vulnerable if those models die early.

What is the difference between Chaos Space Marines and loyalist Space Marines?

Chaos Space Marines mostly use older marks of power armour and field daemon weapons, Possessed, daemon engines and gifts of the Chaos Gods. They trade the loyalists’ discipline and newer technology for raw Warp power and ten millennia of hatred.

Are World Eaters, Death Guard and Thousand Sons part of the Chaos Space Marines army?

In the lore they’re all Chaos Space Marines, but on the tabletop they’re separate factions with their own codexes and model ranges. The Chaos Space Marines army covers the Black Legion, Word Bearers, Iron Warriors, Night Lords, Alpha Legion and renegade warbands such as the Red Corsairs.

What does Heretic Astartes mean?

It’s the official name for Chaos Space Marines, as opposed to the loyal Adeptus Astartes. Games Workshop uses it as the faction keyword and grouping for the Chaos Space Marines, World Eaters, Death Guard, Thousand Sons and Emperor’s Children armies.

Related Content

• 40k Factions Ranked — Competitive tier list
• 40k on a Budget — Start collecting cheap
• All Factions Guide — Every faction explained
• How to Play 40k — Beginner rules guide