The S-Tier Heresy: The Complete Guide to Beating Chaos Space Marines

People have been asking a guide to playing Chaos Space Marines. CSM are my favorite army , so why not? I thought that was a great idea, so I started working on this article last week after getting back from the World Championships.

Unfortunately, I quickly realized there was a serious issue with this plan. Chaos Space Marines are one of the strongest armies in the game already. We, as a community, don’t need a guide on how to play CSM. We need a guide on how to beat CSM.

Here at Warphammer we’re for the people, so let’s have some fun with this. Welcome to the official Warphammer guide to beating 10th Edition Chaos Space Marines.

Whether you play a Chaos army or only play against them, you’ll love the friendly and knowledgable Warphammer community. Come say hi today! https://discord.gg/xetFAuqx3q

Approach to this Guide

Before we get started, let’s address a few points.

Not Every CSM Build Is Too Strong. Some Are Actually Pretty Bad!

As someone who has many thousands of points of currently awful CSM units on my shelf and is desperate for them to get some buffs, I definitely get why some CSM players might bristle at the idea their faction is too strong. I’ve added this section after the article was published because of some feedback I got from CSM players, which I appreciate.

I think some CSM players might take offense to the idea is too strong because they’re not running the “meta builds”. And honestly, there is truth to that. CSM are definitely not like release 10th Edition Eldar or 9th Edition Dark Eldar, where they had a truly endless roster of insanely powerful units. CSM have some particular combos that are overtuned. But if you’re someone who has been running a lot of Daemon Engines or themed lists like max jump pack guys to represent your love of Night Lords, your list is not overtuned. In fact, it may actually be undertuned!

This article is coming from the perspective of strong competitive players running the “best list of a faction” vs “best list of another faction”. If someone is running an optimized list of another faction and faces a Red Corsairs themed list full of Bikers or an Iron Warriors themed list full of Havocs and Legionaries, they don’t get to complain about CSM being too good.

Please don’t get mad at me, fellow CSM players. I love this army, have loved this army since I’ve started 40K, and can’t wait for our busted combos to get nerfed and our underused units to get buffed so we can run whatever we want and not have a target painted on our backs.

The Goal Here is to Give You Tools, Not Solve Every Matchup

The goal here is to set you up for success regardless of specific shifts to your army’s lists or general meta.

I want to give you a framework to improve your decision making in game, and plays to include in your toolbox. I also want you to understand the limitations of CSM, and weaknesses you can exploit.

We’re not going to spend a lot of time talking about exact armies or units to bring to counter CSM because that’s not as important. The issue with that is also while CSM are a top tier army, they’re so far ahead of everyone else that you can hard tech for them at the expense of other matchups. I’m also not an expert on every army in the game. I am an expert on CSM (and most Chaos armies), so I’m going to stick to speaking on topics I know well and let experts of other factions handle guides to playing those other factions.

Why Are Chaos Space Marines So Strong?

For anyone that doesn’t have a lot of experience playing with or against this faction, I’m going to lay out a quick summary of why they’re so strong. This will make sure we’re all on the same page about the issues we have to deal with.

• Undercosted Units
  • This isn’t something you can do anything about in game, but it’s worth mentioning. Chosen, Chaos Lords and Accursed Cultists all need a 10% bump. Warp Talons and Oblits might also warrant a 5-10 point bump.
  • Forgefiends are also a great example of why sometimes free wargear causes huge balance issues. A Forgefiend with triple Plasma is probably worth more than 180 points. A Forgefiend with 2 autocannons and the melee jaws is worth 130 or 140 points at most. Forgefiends probably need a 10-15 point nerf for the health of the game, but that just means people who built their model “wrong” get screwed over even harder.
• Dark Obscuration
  • This stratagem lets any unit get Stealth. This part is okay, but minor.
  • If the unit has the Nurgle mark, that unit basically gets Lone Operative and cannot be targeted from more than 12″ away. This part is the real headache for opponents.
• Profane Zeal
  • This stratagem lets any unit reroll 1’s to hit and wound. This part is okay, but minor.
  • If the unit has the Undivided mark, that unit gets full hit and wound rerolls. This is very, very spicy. What elevates it over the top is that very cheap Undivided Chaos Lords can attach to Undivided Chosen squads and let them spam Profane Zeal once per round for free.
• Accursed Cultists
  • Accursed Cultist max sized units with an attached Dark Commune are a nightmare to deal with. They’re OC2, regenerate models every command phase (they have the old wording Wraithguard did before Wraithguard resurrection got nerfed to their command phase only), can usually benefit from either Dark Obscuration or Profane Zeal, and advance and charge/get +1 to hit and wound once per game.
• Chosen + Chaos Lords in Nurgle Rhinos
  • Undivided ChosenLord units combining a Chaos Lord and 5 Chosen to spam Profane Zeal coming out of Nurgle Rhinos are very fast and powerful missiles that can be launched from relative safety.
• Dark Pacts and Marks
  • The ability to get Sustained/Lethal hits on command is powerful, and is especially powerful when they have the right mark and get get Critical Hits on 5’s in addition to 6’s.

Dealing with Dark Obscuration (And Phantasm, and Mists Of Deimos, and Whatever Super Busted Future Stratagem Comes Out)

In this section we’re going to talk about Dark Obscuration, probably the defining stratagem of 10th Edition Chaos Space Marines. But while we’re talking about Dark Obscuration, we’re not just talking about Dark Obscuration. The same ideas in this section also apply to Phantasm and Mists Of Deimos and any other egregiously strong reactive stratagems GW releases in the future.

You’re All In, or You’re All Out

The way you get most screwed by reactive stratagems is committing to one play and letting your opponent have an easy decision to counter that one play. If they have one unit exposed and you line up all you guns on that unit, they are going to get insane value out of Dark Obscuration.

You have two ways you can respond. You can either not target anything, or you can line up multiple valuable targets and go “they can’t Dark Obscuration everything”. You want to set up units with angles to multiple units so a unit’s shooting isn’t wasted if it can only see one thing and they Dark Obscuration it.

You also want to create situations where it’s so painful in terms of VP if you shoot a target that they can’t use Dark Obscuration to protect valuable material, or vise versa.

The Order of Activations Is VERY Important

When you’re against a strong reactive stratagem that can be used to protect 1 unit, it becomes a battle of information. The CSM player would love to have complete information about where you’re going to shoot everything so they can make a perfect decision on what to use Dark Obscuration on. You want to wait as long as possible in the shooting phase to make decisions that let them commit Dark Obscuration one way or another.

You want to active units in the order that gives up the least information. If a unit only has 1 target then the CSM player has complete information about where its going to shoot, so you’re not giving them any extra information by shooting it. You’ll either prevent your unit from being useless that shooting phase, or force them to spend CP on Dark Obscuration right away and make the rest of your shooting phase much easier.

For all the (justified) ribbing the “less lethal” moniker of 10th Edition gets online, it is pretty rare in 40K to have situations like, “If that unit X gets one shooting activation vs valuable unit Y, unit Y is dead”. Because of this, the CSM player can sometimes let you shoot 1 or 2 units at one of their units before deciding to Dark Obscuration it. This effectively “wastes” the shooting of the first few units that fired but didn’t kill it. So units that have high upside shooting that have a reasonable chance to one-shot one of their Nurgle units is very valuable.

Battleshock Is Weirdly Relevant

Things that force battleshock are also weirdly good into Dark Obscuration. Let’s take, for example, Plagueburst Crawlers. The CSM player might have a unit of Nurgle Cultists on the back objective and you have 3 PBCs. They normally wouldn’t care if you shoot one or two PBCs, because you probably need all 3 to wipe the unit out and they can wait and see how many the first or second PBCs kill before deciding to Dark Obscuration. But because Plaguebursts force Battleshock tests, letting 1 unit shoot might be the same as letting all 3 units shoot because they might lose the ability to use Dark Obscuration. This forces them to use Dark Obscuration when you select the first one to shoot, letting all 3 PBCs shoot their mortars with full information at other targets.

Fast Shooting Is Powerful

I’m thinking back to a game I played vs T’au where they missiled out Piranhas to shoot out my Rhinos on GW terrain, and how effective that was. Piranhas are fast, dirt cheap, and have a roughly 50% chance of one-shotting a Rhino. The T’au player can send a Piranha to get within 12″ to try to pop a Rhino. If it succeeds, awesome. If it fails, its not a big deal. It’s a minor loss of points, and the CSM player still has to send something to deal with it or let you pull the slot machine again.

If You Can Bait Out the CP Expenditure Without Risk, Do It

If you can safely force them to spend 1CP for Dark Obscuration, do it. If you have to expose a unit that will get destroyed next unit just to bait out Dark Obscuration, don’t do that. But look for shooting angles where you can target something like a Redemptor into a Rhino at an angle where they won’t shoot you back with something big. You say you’re going to shoot, they say no thank you, and they are down a CP that would have turned into something spicy later. Zero cost to you, some cost to them.

Dealing with ChosenLords

Let’s talk about ChosenLords. This is a combination of an Undivided Chaos Lord and 5 Chosen. The Lord can once per game get +1 Strength/Attack/AP/Damage in melee, and the whole unit can advance/fall back and charge because of the Chosen’s datasheet rule. The Chaos Lord lets them use Profane Zeal for full hit and wound rerolls for free, which is especially impactful on the Chaos Lord’s Devasting Wounds hammer.

Their Threat Range is Very Unreliable, and the CSM Player Doesn’t Want to Send Them Super Far

Their threat range is usually 3″ from disembarking + 6″ movement + up to 6″ advance + up to 12″ charge roll, so 27″ inches.

Most CSM lists have no way to increase their advance rolls, auto-6 their advance rolls, or increase their charge rolls. The Master Of Possessions does that, but he’s way worse than a Chaos Lord as a Chosen leader so you don’t see him. That means the tail end of their threat range is extremely unreliable.

A World Eaters unit can auto-6 their advance roll and then get +1 to charge from Angron. If your unit is max advance and charge threat range from their unit (so Movement+6″ Advance+11.9″ away), the World Eaters unit can reliably have a 17% chance of making that charge. That’s not great, but it’s large enough you have to consider it. If your unit is max advance and charge threat range from a ChosenLord unit, that ChosenLord unit has a 0.4% chance of hitting a 6 on the advance roll and then making that charge.

Basically the exact math is irrelevant, but the main point is important. CSM on the tail end of their threat range are way less consistent than most other melee armies, so good players are not going to go for those plays.

If a CSM player says “The threat range of my Chosen is 27 inches, do you want to stay 27.1 inches away?”, that’s basically a bluff and you can ignore that. You’re giving up board position for no reason.

Don’t Let People “Cheat” with Disembarking

I’m going to put “cheat” in quotations because actual intentional cheating is vanishingly rare, but many players are getting away with extra movement from units out of transports that can sometimes be very impactful. What people do is know the unit disembarks up to 3″ away and then moves 6+d6″ inches, so they go directly to setting up the units 3+6+d6″ away from the transport. Make them disembark, set up the unit wholly within 3″ of the Rhino, and then roll the advance and move the unit.

The key issue is that depending on what your advance roll is, they might want to put the Chaos Lord (who is the squad’s real damage dealer) in a different spot. If they roll a 1 on the advance, maybe they want the Chaos Lord on the side facing the closer unit. If they roll a 6, they’re now in range to charge something more valuable on the other side so they want the Chaos Lord on the other side. People also accidentally move the back models in the squad too far when they do this. I see the following situation all the time.

Remember That Units Coming Out of Destroyed Transports are Always Battleshocked

If a Transport is destroyed, the disembarking units are Battleshocked for the rest of the turn. This is very relevant for ChosenLords, because the way you get to them first is often by destroying a Rhino and then trying to get them.

If you destroy the Rhino in shooting and then line up other shots on the Chosen that got out or plan to charge them with something else, they cannot use the Chaos Lord’s ability to get Armour Of Contempt for free because that unit is battleshocked. If you destroy the Rhino in melee with one unit and will use another unit to pile-in and fight the ChosenLords that got out, they cannot use Eternal Hate to 4+ fight on death or spend 2CP to interrupt in melee.

You can also set up wraps on the Rhino. It’s trickier than it used to be and sometimes requires a fair bit of models, but you can ensure some models die in certain situations.

Dealing with Accursed Cultists

Accursed Cultists are very difficult to deal with for a few reasons. The combination of 5++ invuln and 6+++ Feel No Pain makes them weirdly durable. In addition, because they have a mix of 1 wound and 3 wound models, they can switch their wound allocation around to tank meltas on the 1 wound guys and bolters on the 3 wound guys.

Don’t Bother Shooting Them Unless You Can Do Real Damage

Literally the ideal situation for an Accursed Cultist player is for you to shoot and kill a few models, because they can resurrect up to 3 little guys or 1 big guy and get 2-3″ of extra movement towards an objective or charge target. In fact, because they can resurrect in both command phases, they can resurrect up to 6 little guys before your next shooting phase, getting 5-6″ inches of extra movement.

This applies to all resurrecting units, not just Accursed Cultists, but they’re the most prominent one right now. Stay disciplined and don’t do chip damage to units that might want to go for aggressive plays later, because it won’t stick and just gives them extra movement.

Bring Volume Firepower

I’m very much aware CSM are legitimately too strong and I don’t want to be like those Dark Eldar players in 9th Edition who delusionally insisted their army was only busted because other armies didn’t bring autocannons or chainswords, but the fact is Accursed Cultist bricks are a real force in the meta. You don’t want to be entirely unprepared.

You want some sort of option in your army to deliver a massive volume of attacks in one activation. Units like 10 Berzerkers, 10 Shadow Spectres (especially with Guide), and units of 6 Crisis Suits will one-shot an Accursed Cultist brick or whittle them down to irrelevancy for a long time.

Make Them Declare Their Once Per Game Powerup in the Command Phase

I will go out of my way to ask them if they want to use the Dark Commune’s ability before they move any models. This is because once they see their Advance roll, they’ve gained a massive amount of information that can sometimes inform whether they would have wanted to advance and charge. This decision is made before they roll their advance, not after. This is in contrast to the CSM Slaanesh stratagem, which can be used to advance and charge after rolling an advance.

I want to make sure the spirit behind this section is very clear. It is not to catch them moving one model elsewhere and then maniacally laugh and say, “you fool, you buffoon, your command phase is over and you can’t use that ability anymore”. I’m extremely lenient with takebacks if people forgot some ability, and often go out of my way to remind them myself.

But if they’ve gained information about a roll in a later phase that would directly inform a decision in an earlier phase, it is very reasonable to deny them the chance to use that earlier ability, or at the very least insist they reroll the advance roll.

Try to Precision Out Characters

The Demagogue in the Dark Commune that gives the entire squad a 5++ invuln is just a little goober that’s easy to kill. The issue is a good CSM player is aware the counter to Accursed Cultists is Precision, so they’ll keep that specific model tucked away behind a wall to counter your counter.

A trick I like to use is sending in a melee squad with a Character and then using some fight phase movement tricks to get that Character peeking behind a wall. If your Character is within engagement range of the Accursed Cultist brick by being base-to-base of another model basing some Accursed Cultists but the tip of his sword is facing backwards and peeking around the corner of a wall to see the Dark Commune on the other side, you can Precision him out. This doesn’t work for every situation and is sometimes dependent on your change roll, but you can do some spicy stuff with move-blocking your own models to get your Character in perfect positions.

One important sportsmanship note: If you’re going to do some very technical Fight Phase tricks, it’s a great idea to be completely open about the trick you’re going to use and let your opponent confirm its possible (or argue against it) before you move any models. I’m thinking back to a situation I had in a game vs David Gaylard at the World Championships, where I rolled a charge and saw a possibility to swing a specific model in my squad in an unintuitive way to fight a nearby Character I hadn’t declared as part of the charge. Before I moved any models for the charge, I told David where they were going to move in the charge, which models of his would be closest to which models of mine, and then where they were going to move on the pile-in. This gave him the chance to double check everything was possible. He said some of the precise measurements were too close to call and recommended we call a judge. I thought that was a great idea. We were playing a very friendly game and neither of us wanted to get bogged down arguing over tiny measurements. We just wanted to know if the play was possible and keep the game moving. The judge confirmed it was possible, and I moved forward with the plan and killed the Character.

If I had just quickly moved the models after my charge without confirming every future movement was possible, my opponent would have been justified in questioning the situation. It also took a lot of pressure off of me to move every model precisely down to the millimeter, because we had confirmed where every model was going to end up already.

Dealing with Dark Pacts

CSM can choose to make a Leadership Check when a unit activates. If they fail the leadership check, they take d3 mortal wounds. Regardless of the result of the leadership check, their unit gains Sustained Hits or Lethal Hits. Depending on the Mark, they can get Sustained or Lethal on 5’s instead of 6’s.

Overwatch

First thing to be aware of: CSM can Dark Pact in Overwatch. If you’re doing the mental math to figure out how much damage your unit will take in overwatch, basically double it because they’re going to have Sustained Hits. If the unit is Undivided, they’re going to have Sustained Hits and reroll 1’s to Hit. Do note that Nurgle units cannot get Sustained Hits on 5’s in Overwatch, as overwatch always requires unmodified 6’s to succeed unless an ability explicitly states otherwise.

There’s really no specific way to deal with this besides just good general tips and tricks on avoiding Overwatch. Be very careful if you have some elite infantry moving or charging in front of a Forgefiend, because the damage is good on average and is brutal if they spike their 6’s.

On that note, if they’re Overwatching with a Forgefiend, make sure they choose whether they’re using the Hazardous ability before they roll dice. If they go full Dark Pact + Hazardous, it’s hilarious how often they do more damage to themselves than you.

Remind Them To Do Dark Pacts Before Moving On, or Agree to Let Them Roll Them Before Shooting

Just being entirely honest: As a CSM player, I have forgotten to do my Dark Pacts plenty of times. I normally remember at the end of the Shooting Phase and do them all at once, but I’m sure some Dark Pact tests have slipped through the cracks before.

What I do as a CSM player now is roll my Dark Pacts before my unit shoots so its impossible to forget. It technically happens afterwards, but it doesn’t matter as long as both players know what’s going on. If your CSM opponent is forgetting to roll their Dark Pacts (or “forgetting” to roll their Dark Pacts), propose that as a solution.

CSM are so busted I refuse to play them, My Army Doesn’t Have Access to Every One Of These Plays So You’re Saying This Matchup Is Hopeless?, *Cries In [Low Tier Army]*

Go cry about it in your faction-specific discord groups or FB groups like you already do every day.

I don’t even bother interacting with these kind of low effort dooming comments anymore, it’s a real drain on everyone’s enjoyment of 40K.

What Units Are Good Into CSM?

Let’s talk about a few types of units that are good into CSM, and some examples so people can see what we’re talking about.

Fast and Deadly Shooting

CSM like to connect with units that stay still in front of them. Armies that can shoot very well while being very mobile can be a big headache. You want the speed to get within 12″ to prevent Dark Obscuration from being used while being able to line up guns on the points where Chosen will disembark. You want to be able to line up guns wherever the CSM player is weak. Quality artillery is also an issue for CSM, because then they can’t perfectly stage Warp Talons to harass you with impunity.

Examples: T’au, some Marine builds, some Necron builds

Vect Abilities

Any ability that makes a Battle Tactic cost extra is painful for CSM because they love to spam Profane Zeal to turbocharge their damage output. Even on units that aren’t usually Undivided like Nurgle Forgefiends, rerolling 1’s to hit and wound makes them much more reliable.

Examples: Cypher, Kairos

3″ Deepstriking Dangerous Units

CSM, as an army, love to keep the enemy in front of them and keep driving forwards.

The biggest danger for those kinds of lists are dangerous units that can deepstrike close-by and unleash huge amounts of damage. I would say deepstriking damage in general is pretty good, but there is generally enough cheap units in CSM lists to screen out 9″ deepstrikes if the player actually cares in that matchup. 3″ deepstrike is much more reliable against good players.

People forget it now because GSC have gotten nerfed pretty hard since then, but GSC were just an absolutely abysmal matchup for CSM for a large part of the edition because of how those armies interact. That’s still more true than not.

Examples: Plasma Inceptors, Hypercrypt, GSC

How I Would Nerf (or Buff) CSM

The big issue with nerfing CSM is their strength comes from how the Dark Pacts, Stratagems, and undercosted units all interact. I worry people are going to call for big points nerfs to some key units and then also call for nerfs to Profane Zeal and Dark Obscuration, not understanding that a nerf to those strats is already a big nerf to those respective units.

If I had to balance CSM right now, here is what I would do:

• Nothing in a vacuum. CSM do need an overall power nerf, but I’d want that to happen at the same time as other top tier factions receive nerfs of varying degrees and bad armies get buffs. Eldar are still one more good hit from being balanced, and I’m very worried about Necrons running wild if some key units like Wraiths are unnerfed when their points come out.
• Dark Obscuration/Nurgle Interaction Nerf. Nerf Dark Obscuration’s Nurgle effect to only take effect at 18 inches. This should also come with a game-wide nerf to similar abilities, because they’re basically all silly and un-interactive.
• Profane Zeal/Undivided Interaction Nerf. Nerf Profane Zeal’s Undivided effect to only be full Wound rerolls, not full Hit rerolls. This is a nice nerf for multiple reasons. One, it’s a big nerf to ChosenLords as they hit on 3’s. It also makes Undivided Forgefiends less reliable. Two, it makes Abaddon more important for Undivided builds. I don’t want Profane Zeal to become Hit rerolls only because then the irony will be Abaddon will be least effective with Undivided units, when he’s the Warmaster of Chaos Undivided! If you pay 310 for Abaddon and stay within 6″ of him and spend 1CP on nerfed Profane Zeal, you still get full Hit and Wound rerolls. That’s a much more fair investment for that level of power than spending 1CP whenever or wherever.
• Points Nerfs to Key Units. Chosen point buff reverted, Chaos Lords + 10, Accursed Cultists +10 per 8 models, Warp Talons +5, Forgefiends +10, Rhinos +5. Basically all of these units rely on Profane Zeal and Dark Obscuration, so a nerf to those is already a nerf to them.
• Points Buffs to Bad Units. Venomcrawlers -15, Maulerfiends -15, Vashtorr -20, DiscoLords -20, Heldrakes -a massive amount because all Heldrakes in all Chaos factions are garbage and we need to see flying metal turkeys that required 3 days to paint their trim on 40K tables again.

Final Thoughts

Chaos Space Marines are one of my favorite armies. Weirdly enough, now that they’re on top of the meta, I’m actually playing them a lot less than I used to. CSM are at their most fun when they’re plucky underdogs waging war against a hostile meta.

I want to get to the table about a loyalist Space Marine player and think, “Hell yeah, time to kill as many Space Marines as I can”, not “Damn, I feel bad for killing so many Space Marines so quickly”.

With this guide to beating Chaos Space Marines out of the way, we’re going to resume our usual pro-Chaos content next week. I’m not entirely sure which half-finished article I’m going to finish up and publish, but I do know that we’re going to continue fulfilling our promise of 1 article a week for the next month.

As always, have fun, stay safe, and may the Dark Gods bless your rolls!