Goonhammer Reviews Warhammer 40,000 10th Edition – Part 1: The Core Rules

You’ve been waiting for months, and it’s finally here: the tenth Edition of 40k. Promising a simplified (but not necessary simple) rules framework, more clarity than ever, and a complete overhaul of unit rules, this new edition is poised to be the best one yet, taking everything learned over the last three years of 9th edition and giving us the tightest rules yet.

In this multi-part series we’re going to go through the game rules, how 10th edition is played, and offer our thoughts on the good and bad of that plus some tactical insight every step of the way. There’s a ton to cover here so we’re breaking it up into more manageable chunks to make it easier to read and browse. For quick navigation, you can use the links below (links will be added as articles are published):

In this article we’re going to give the overview of 10th edition – the good, the bad, and what you need to know in a nutshell – and we’ll talk about changes to the core rules and the way players muster armies.

As always, thanks to Games Workshop for providing a preview copy for purposes of this review.

Tenth Edition in a Nutshell

Tenth edition, while having some key changes that improve the game in any number of ways, is still recognizably the same Warhammer: 40,000 we’ve all been playing for the last few years. If you’ve been happy enough throughout 9th and are mostly hoping for some tweaks here and there to improve the experience, this book will go above and beyond, and you’re likely to have a blast with the new edition. If, on the other hand, you just hated 9th, there might not be enough here to get you on board: the game still feels a lot like 9th, and the changes that they’ve made, while substantial, aren’t going to transform this into a completely different game (at least, not in terms of their core – the army and mission rules are a different matter and may change your impression).

But if you’re like many players who found the core ideas underlying 8th and 9th edition appealing, but just couldn’t get behind the execution, this edition is definitely worth a shot. Many of the common pain points people have articulated about 9th–things like the sheer volume of rules, ease of reference, and consistency and creativity in missions–have been significantly changed, and nearly uniformly for the better. Many of the changes aren’t as drastic as, say, the ones that came with the shift from 7th to 8th, but they do feel substantial and intentional, and are likely to make the game a lot more fun for new and returning players alike.

Credit: Games Workshop

What’s New

There’s a ton of new stuff, but here are a few of the biggest things you need to know about the new edition:

  • Army construction is easier than ever. The big theme of 10th is “simplified, not simple” and that’s most evident in army construction. Gone are the complicated force org charts and CP generation schemes of prior editions. Now you pick a character and start adding units, with only a couple of restrictions around how you can build your army.
  • Characters join units. Gone are the free-standing characters of 8th and 9th edition; we’re now back to characters attaching to units, though unlike the independent characters of of the past they stay attached to those units for an entire game. There are still auras, but many characters will just buff the units they’re leading.
  • Unit Statlines have changed. 10th edition gives us another overhaul of unit statlines, making them more like Kill Team, with the WS, BS, A, and S characteristics moving to the unit’s weapon profiles. Leadership got an overhaul with a new target number to roll on 2d6, and units now have an Objective Control characteristic used (as the name suggests) to determine control of objectives. More rules also now live on datasheets rather than being applied at the faction level.
  • The Psychic and Morale phases are gone. 6th and 7th editions brought back the Psychic phase, and now it’s gone. Psychic abilities just happen now, and they happen in the phases they matter. No more standing around while your opponent plays with warp charge and Cabal points, and no more worrying about Deny the Witch stopping your powers from having an effect. The Morale phase is also gone, with units taking Battle-shock tests (the new ‘morale’ mechanic, though with a different focus to the prior incarnations) in the Command phase. 
  • Missions have been completely overhauled. The largest single structural change to 10th edition is the missions. In an evolution from 9th, there’s now a single set of missions, which combine the best aspects of 9th’s GT missions with Tempest of War to give players a flexible, dynamic mission system that rewards versatility and the ability to react to changing priorities.
  • Objective Secured has been replaced by Objective Control. The old “obsec” rule created very binary situations, where a unit of veteran murderers could be prevetend from flipping an objective because a single Grot had survived their onslaught, or a towering Knight Dominus was less helpful for holding a point than its Armiger companions. It also encouraged a gamey kind of play where a single obsec model would put the very edge of their base into the control zone of an objective, safe in the knowledge that non-obsec units would be completely unable to steal it away. This has been replaced by a new “OC” stat on every datasheet, which allows for much more nuanced objective play – and also opens up design possibilities that just didn’t exist before.

On balance, most of these changes are good. Players reading the rulebook will find information accessible and easy to understand, with strong layouts, lots of diagrams, and good visual design. More care has been taken with regard to presentation to make things easier to grasp – as an example, Stratagems now have a standard layout, which specifies their timing, targets, and any restrictions around their use very explicitly.

What’s Good?

There’s a lot to like about the new edition, but these are our favorite changes.

  • Simpler army construction. No disrespect to roster builder tools, but their time may have come – army building is no longer the kind of Byzantine process it used to be, and players can spend more time thinking about what they want to take than how to fill compulsory slots.
  • Universal Special Rules (USRs) are back. 10th edition removes one of the weirder parts of 8th and 9th edition, where units would have the same rules with different names repeated over and over on datasheets, and takes us back to having universal special rules such as Deep Strike and Feel No Pain. Unlike the gaudy excesses of the Horus Heresy list, the number of USRs in 10th has been kept tastefully small.
  • Morale (finally) matters. Morale in 40k has been tricky, and through 8th and 9th tended to just function as a way to kill more models – with plenty of exceptions and mitigations that made it pretty unsatisfactory for both players. 10th edition introduces us to Battle-shock tests, which can affect both units and single models, and does so by reducing their effectiveness on the battlefield instead of just killing more of them.
  • Simplified Army rules. Moving to a single two-page “spread” of army rules, detachment rules, and stratagems with more rules on the units really makes things a lot easier to work with while not sacrificing tactical complexity.

What’s Bad?

That said, there are still some things we’re not sure about, or some things that give us pause. The good news is that these can be mostly addressed in future updates and dataslates.

  • It’s still a bit rough around the edges. There are some things here that needed another editing pass, but we’re hopeful a day 1 glossary/faq will help put all of those concerns to bed.
  • Removing actions as a named rule. Actions are still in the game in practice, but more loosely defined as something a unit does instead of shooting. They’ve been reduced in importance quite a bit and it reduces the number of things units can do that isn’t trying to kill other units. 
  • Some risky balance choices. More free-form army building has lots of upside – it’s great for making it easier to build lists you actually want, and to take the units you want to take, and mitigates some of the weirdness around units being good on their own merits but not better than another unit in their slot which you would take instead. However, relaxing those restrictions reduces the need for compromise in list-building, and increases the possibilities for players to just stuff their lists full of skew choices – the maximum toughness, the maximum damage output – which make it hard for more balanced lists to compete.
  • Moving rules to the units creates its own issues. While we’re a fan of the streamlined army rules, the move to unit rules and datacards is more of a mixed bag. A lot of the examples we’ve seen in previews don’t refer to the USRs, and instead to some specific unique thing for that unit – which just means the complexity has moved. It might turn out that it’s not better to have to remember a different unit rule for everything in your army than it was to remember 10 more broadly-applicable Stratagems. 

Credit: Games Workshop

The Core Rules

The 10th Edition rules come in at roughly the same length as 9th edition’s rules, if you include the Glossary and Rare Rules sections from the previous edition, spanning about 45 pages. The rules themselves have been laid out in a much more organic, understandable way, with lots of large diagrams and photo examples. What’s considered “Core Rules” is also now a bit more extensive than in 9th Edition, rolling in Stratagems, Terrain, Army Construction and more – all things which were labelled as “Advanced Rules” before, but were non-optional in practice.

We’ll talk more about the structure of game turns in Part 2 of this series but suffice to say that a round of 40k is going to feel roughly the same as before, give or take a couple of phases. Players still alternate taking turns as they move, shoot, and fight with all their units. Dice are rolled to hit, wound, and save, and models removed have an impact on Morale – though that impact itself is completely different to what came before.

Beyond the top-level alterations to turn structure, the meat of the changes are in how players build armies, where and how rules are laid out (particularly unit datasheets and characteristics), and the missions you’ll be playing with them. There’s a lot to talk about here, and it’s worth saying that although nothing will be that difficult to pick up, there are pitfalls for the kind of assumed knowledge that experienced players of 8th and 9th edition might want to bring forward into 10th. Taking the time to have a really good read of these will help a lot, because there’s some serious differences in the detail which will change what you think you can (and can’t) do.

Core Concepts

The Core Rules kick off with a section called Core Concepts, where they review the key terms and concepts of the game. For new players, this is where they’ll get clarity on what Units, Armies, Datasheets, and Keywords are, and where they’ll learn about Coherency and Visibility. For returning players, there are some big changes here to note.

The first is Unit Coherency, which now requires that a unit’s models be within 2″ horizontally and 5″ vertically of two other models from the same unit if the unit has 7+ models (increased from 6+ in the previous Edition, to allow you to add one Leader without changing your coherency rules). The second is visibility, which plays a much bigger role in the rules.

Key Changes: Determining Visibility

Visibility now includes four states to track, which will most often be important when it comes to determining whether models have the benefit of cover (more on that when we talk about terrain). Note that when determining visibility models can see through other models in their unit, and a model’s base is part of that model.

  • Model Visible and Unit Visible refer to any part of a model or unit (one or more models) being visible to the observing model.
  • Model Fully Visible and Unit Fully Visible refer to states where every part of another model can be seen by the observing model (no models or terrain features block visibility to any parts of that model), and every model in a unit being fully visible, respectively.

Finding Your Rules

The 10th edition rules are about as long as those from 9th edition, with around 45 pages of rules – there’s no pretense of fitting the entire game’s rules into a single pamphlet like with 8th edition – but the rules themselves have been laid out in a much more organic, understandable way, with lots of large diagrams and photo examples. In addition to the game’s core rules, there are also Stratagems and Universal Special rules in the book.


One of the most common complaints about 9th edition was the sheer number of different stratagems available to each faction. With the right combination of faction, sub-faction, and/or Army of Renown, it was possible to end up with 50-60 different choices spread across two or three books, many of which didn’t come up that much or only applied to a small category of units – or even just a single datasheet – plus many others which were only used during army construction.

10th edition completely transforms this situation. There are now 11 core stratagems, included in the core rulebook and common to everyone. Beyond this, each player will have 6 stratagems specific to them, which are part of the detachment they’ve selected. These are all neatly presented on the datacards which summarize the entire detachment, and that’s it. There are no other stratagems to remember, nothing stuffed into a supplement to a supplement that you had to buy even though you only need two pages of it. You can of course have different stratagems if you pick a different detachment (although exactly how different isn’t clear to us yet – some of the ones previewed on Warhammer Community over the last few weeks look like the kind of load-bearing ability your faction would really rely on having no matter what), but the model for 10th edition is a “one in, one out” system – you don’t ever get more stuff for playing a particular way, just different stuff. That means you shouldn’t ever have more than 17 different stratagems to pick from, and most of those are core stratagems that your opponent will be using too. This is a huge decrease in cognitive load, giving both players much less to think about. It’s also a real strength of the datacard format, because if your opponent doesn’t know your rules they don’t have to flick through 2-4 pages in multiple supplements and try to guess which ones actually matter – you can just hand them the datacard, and that’s all the information they need. We’ll talk more about these Core Stratagems in their own section in Part 2: Playing the Game.

The Return of Universal Special Rules

In addition to stratagems, many of the most common rules you’ll see have been codified into universal rules that can be referenced by various armies. Gone are the days of 8th and 9th edition where the Genestealer Cults’ Death From Below, T’au Empire’s Manta Strike, Necrons’ Dimensional Translocation, and any other number of creatively-named rules were all just white-labled versions of the Space Marines’ Teleport Strike (itself sharing a codex with Death From Above, again providing the same effect). Instead, everything that starts off the board and then shows up during your Reinforcements step now has Deep Strike. Similarly, common weapon abilities like “unmodified 6s to hit cause additional hits” or “can be fired at targets without line of sight” have been significantly cut down to Sustained Hits [X] and Indirect Fire respectively.

Admittedly, this change means that many weapons will now require you to refer back to the core rules to know everything about how they work. Fortunately, they’ve shown decent restraint with the number of universal special rules, and things which previously were game rules have been moved to this category – for example, weapon types such as Assault and Heavy have become keyworded weapon abilities, so remembering those is about the same. The fact that every list is now going to be drawing from the same pool of weapon keywords also means that once you’ve learned what those keywords do for your army, you’ve learned them for everyone else’s. These weapon abilities are all helpfully outlined in a three-page spread in the book just after the rules for the Shooting phase.

On the other hand, the remaining USRs are a bit harder to find – it’s a bit annoying to look up universal datasheet abilities, like Stealth, or Deadly Demise. While the universal rules for weapons are all in one place, the others are scattered throughout the rules. You can kind of guess where they might be, and there is an index at the back with page references, but it’s not as clean as the weapon rules which are neatly grouped together.

In some cases that guessing game will be enough to get you where you need to go – Deadly Demise, for instance, causes a unit to have a chance to explode when it takes enough damage to be destroyed and, sure enough, it’s right there at the bottom of the rules for inflicting damage on a unit. For other rules though, this setup sucks. Attaching a character to a unit with Leader has huge impacts on multiple stages of preparing for and playing the game, from mustering your army, to deployment, to allocation of wounds in the shooting and fight phases. But the first time that rule is discussed is in the section on “Deployment Abilities,” which doesn’t appear until after the book has moved on from the rules of playing the game into how to read a datasheet. For other rules, like Stealth, the name isn’t very helpful in locating it: if I didn’t already know that it affects shooting, how would I know to look in the rules for making ranged attacks to find out that it imposes a -1 to the hit roll?

This is especially frustrating given that there’s an entire section called “Datasheets and Unit Abilities,” and that section only actually contains four of the eleven unit abilities appearing in the book. They could have easily printed all the abilities here, or at least re-printed them so there’s a definitive source of them. Instead, you’re left having to either remember where to find it, or check the index if you can’t. As it stands, these rules are absolutely screaming for a summary sheet, and the fact that this book doesn’t have one is honestly one of its biggest shortcomings. A USRs summary sheet would be a great add for future mini-rulebook printings or to package with datacards – or, in this new digital world where the core rules are apparently going to be available online, in a PDF format.

Credit: Games Workshop

Mustering an Army

Before you can play, you need to muster an army to play with. Building an army for a game of 10th edition is easier than ever. You can break the process down into five key steps:

  1. Determine game size
  2. Pick a faction
  3. Select Detachment Rules
  4. Pick units and Enhancements
  5. Nominate a Warlord

1. Determine Game Size

You and your opponent first agree on a size of game, selecting from Incursion (1000pts), Strike Force (2000pts) or Onslaught (3000pts). You can, of course, vary these sizes, but for significantly smaller games it’s recommended that you play Combat Patrol, a streamlined mode designed to get players started with the contents of (as the name suggests) a Combat Patrol box set (more on this mode in its own separate article, as trailed earlier). No one is stopping you picking whatever size you choose, however, and if you choose a size that’s in between two of the suggested ones, we’d recommend you just use the rules for the higher of those two for things when it comes to rules such as Reserve limits.

2. Pick a Faction

After picking a size, each player selects two things – their Army Faction, and their Detachment Rules. Army Faction sets the Faction Keyword that all units you select need to have, which appears in the bottom-right of their Datasheet. It also activates an Army Rule that will appear on most of those units’ Datasheets. We’ve seen most of these previewed on Warhammer Community, so go and take a look at the preview for your Faction to get a flavour for what these are like. Some rules we’ve seen previewed (e.g. Daemonic Pact) let you include units with a different Faction in your army, and it’s worth remembering that when you do this they will not benefit from their Army Rule, even if it’s on their Datasheet – only the Army Rule for the faction you select is active. This ends up feeling vastly cleaner than previous implementations of this – no more wondering if the precise wording of the rule you’re using to import other units breaks your army rules or not – the rules for your Army Faction are active, full stop.

3. Select Detachment Rules

Next, you select a set of Detachment Rules, which provide you with an additional rule applying across all your units, and access to a set of Enhancements (upgrades you can buy for CHARACTERS) and Stratagems (in-game effects you can spend Command Points on). Once again, most of these have been previewed in the various Faction Focus articles, and our understanding is that for most armies there will only be one of these to select from on launch, and that more will be added in the future. Detachment Special Rules usually only affect models with the Faction Keyword from the army they belong to, so once again any units you’re sneaking in via other means aren’t going to benefit from these.

4. Pick Units and Enhancements

With all that in place, it’s time to pick some Units and Enhancements. This is pretty freeform, meaning that pretty much any collection will be able to be turned into a valid list. Your army must include at least one Character, and from there you can do pretty much whatever you want. You can only include a maximum of three of each unit, unless they have either the Battleline (in which case you can take six), Dedicated Transport (again six, but each must have a unit start the game embarked) or Epic Hero (the new term for named – and therefore unique – characters) keywords. 

You can also purchase Enhancements – the 10th edition equivalent of warlord traits and relics – for up to three of your Characters (excluding Epic Heroes), each of which must be unique.

5. Nominate a Warlord

Last up, you select one Character from your army to be your Warlord, and they gain the WARLORD keyword, which some rules interact with. 

This whole process is nice and simple, though going very free-form does open up the possibility of players finding powerful skew lists. On the upside, it avoids an issue which sometimes arose in previous editions where some factions actively wanted to include the “glue” units that made their army legal, while for others they were basically a tax.

Key Changes: Army Construction

Army Construction is easier than ever, with fewer restrictions on what to bring and fewer hoops to jump through.

  • Force Org Charts are gone. Now you just pick at least one character and any combination of other units, with a maximum of 3 per datasheet, unless that unit is either Battleline, a Dedicated Transport, or an Epic Hero.
  • Warlord Traits and Relics are gone. Armies can now purchase up to three Enhancements for their characters, which cover both categories, and these cost points rather than being something you spend pre-game Command Points on.
  • Subfactions are gone. They’ve been replaced by Detachments, which now dictate both new rules for your army and also the Stratagems and Enhancements you’ll have access to.

Units and Datasheets

8th edition introduced us to Datasheets and 10th edition further refines the formula by really going “all in” on the concept. Every unit has a datasheet that lists the characteristics, wargear, abilities, and keywords of its models. And while conceptually these are very similar to those of the past two editions, there are a number of major changes here which make them easier to read and work with.

In addition to a unit’s rules, datasheets also tell you what the unit composition is and how they can be armed, essentially giving you the info to play with the unit one one side and the important information for army building on the other. It’s a smart way to lay things out and makes the datasheets themselves an invaluable reference to have on hand during games.

Key Changes: Datasheets

Datasheets have been greatly streamlined in 10th edition, and contain everything you need to know rules-wise about playing with a unit aside from its Army and Detachment rules.

  • Fewer Characteristics. Units now only have Movement (M), Toughness (T), Save (SV), Wounds (W), Leadership (LD), and a new characteristic, Objective Control (OC).
  • Leadership is now a target roll on 2D6. Units will have Leadership values such as “6+”, indicating that in order to pass a Leadership test they must roll a 6 or better on 2D6.
  • Objective Control is all-new. The Objective Control characteristic is used to determine control of objectives during a mission. Higher numbers mean the unit is better at controlling objectives on a per-model basis. Most infantry have OC 1 or 2 while vehicles and monsters may have 5 or more.
  • Strength, BS/WS, and Attacks have been moved to the weapons. Every datasheet includes the weapon options for the unit, and each of these outlines how many attacks the unit gets per model as well as the Strength, AP, Damage, and WS or BS of those attacks. If you’ve played Kill Team, this will be very familiar to you.
  • Unit Abilities. Units now have a mix of abilities on their sheet, categorised by where they’re from. Core abilities are rules you’ll find in the Core rules such as Deep Strike, while Faction abilities are the rules they get for being in a specific faction, such as Oath of Moment or Strands of Fate. Each datasheet then has some number of bespoke special abilities unique to that unit or a small number of units, like the Land Raider’s Assault Ramp rule. We’ll cover these more in future articles on the individual indexes, but anyone reading the WarCom previews will already have noticed that every unit has at least one of these rules on its datasheet.

Building the Battlefield

9th edition made some very significant changes to the terrain rules compared to 8th, largely in the sense that it had meaningful rules for terrain at all. 10th takes the better parts of these and ditches the weaker ones, changing how units interact with terrain and what benefits they receive. The Core Rules provide four pages of example battlefields to play on for Strike Force and Incursion games, though anyone who has played competitively will at minimum look at these with an eyebrow raised.

Terrain and Visibility

As with prior editions, your battlefields will typically be populated by a number of Terrain Features, many of which can provide the Benefit of Cover. While you have the Benefit of Cover (shortened to Cover from here on), you add 1 to your saving throws. There’s no intrinsic limitation to who can receive this, but some terrain features only grant Cover to certain models. In addition, if you have a Save Characteristic of 3+, you cannot gain cover against AP0 attacks – presumably intended to reduce the amount of time spent on shooting that will do almost nothing, and also to ensure that your power-armored badasses don’t spend all game cowering in ruins to avoid lasgun fire.

In order to determine whether units or models get Cover from a terrain feature, it’s often necessary to check whether they are Visible. We covered this above in greater detail but note that at any given time, a model or a unit can be either not visible, visible, or fully visible to an enemy model. 

Most terrain features allow a model to gain cover if it is not fully visible to every model in the attacking unit due to the terrain feature. This ends up meaning that you’re quite often going to be able to claim Cover on some models from a terrain feature, and it’s particularly easy to do so against large enemy units. It also neatly avoids some potential pit traps of having to work out how many models in the target unit are fully visible to different sets of models in the firing unit, which could create a huge headache while resolving attacks, and it also means that Fast Dice Rolling is going to be possible most of the time for any step except the saves, which can still be quickly processed in batches. It also means that Vehicles and Monsters will have Cover a lot more than was the case in 9th Edition and (as we’ll see) gives some kinds of Terrain Feature far more utility than in the previous Edition. A couple of Terrain types also apply some changes to how Visibility works, making it easier to claim Cover from them, or perhaps to be hidden entirely.

There are six types of terrain feature in the book, four of which we can blast through pretty quickly. Unlike in previous editions, none of these impose any penalties to the Movement characteristic of units passing through them, and models can move through anything less than 2” tall as if it was not there. Any taller than that, and you need to measure vertical distance to climb up and down (or measure up diagonally if you FLY).

The four “simple” terrain features are Craters/Rubble, Barricades/Fuel Pipes Battlefield Debris/Statues and Hills/Containers/Sealed Structures. Each of these categories gets a keyword we’ll use from here on, and these are Crater, Barricade, Battlefield Debris and Hill. Craters are also Area Terrain, which has no intrinsic rules, but presumably interacts with abilities elsewhere, while Barricades and Battlefield Debris are Obstacles. Hills are just there.

All four of these provide Cover under certain conditions. Craters, Barricades, Hills, and Battlefield Debris are all pretty straightforward, while Woods and Ruins are both a bit more complicated, because as well as handing out Cover, they also modify how Visibility is determined.

Craters and Barricades

Craters and Barricades are restricted to INFANTRY – the former grants Cover to any Infantry model that’s wholly within the area, while the latter grants Cover to Infantry models that are within 3” of it, and not fully visible to every model in an attacking unit because of it (as above). Barricades also modify normal rules around Engagement Range, allowing charges to end within 2” of a target as long as they’re on the far side of a Barricade, and models to make attacks up to 2” away over the barricade.

Battlefield Debris and Hills

Battlefield Debris and Hills are functionally very similar to one another, basically being the same set of rules assigned to things that you can’t stand on (Debris) and things with flat tops that can be stood on (Hills). Both provide Cover to any unit that’s not fully visible to every model in an attacking unit because of the terrain feature. This makes hills and random statues massively more impactful on the game than they were in 9th, which is a really welcome change that should lead to a bit more variety in what we see on the table.


Woods (another piece of Area Terrain) are the first of these two, and these make it easier for models that are either within them or on the far side to claim Cover, which they provide in the same way as Hills or Debris, plus to any model wholly within them. While a model is wholly within a wood, it also never counts as being Fully Visible, so will always benefit from Cover, and the same is true for any model where a model observing it has to draw line of sight through or over the wood, so even if the declared area is pretty sparse and doesn’t have many trees in it (common on tournament tables) being on the far side will still provide you with a significant benefit. Aircraft and Towering models are exceptions to this in both directions – they don’t get the automatic Cover from being on the far side, but a sparse wood also won’t protect a target from them (though physical parts of this terrain feature can still hide these models as normal). In terms of gaining Cover, this is all pretty similar to how Dense terrain worked in 9th Edition, but boosting saves will probably end up having more impact on Vehicles than -1 to hit a lot of the time, so may end up mattering more. The requirement to be wholly within also removes the weirdness of a tank sticking the back end of one track into terrain and gaining the benefit of being incover.


Finally, Ruins, staple of tournament tables everywhere. Ruins once again provide Cover in the same way as Woods, so if they’re either partially hiding you or you’re wholly within them, you get +1 to your save. They also go even further than Woods in affecting Visibility to models on the far side of them – you cannot see through Ruins at all, even if the physical terrain has windows etc. Models that are wholly within the ruin can see out and be seen normally, but if you’re fully on the far side of the footprint? No dice. This is similar to Obscuring terrain in 9th Edition, and like there it doesn’t affect Aircraft and Towering models. Like with woods, however, this now works in both directions, so a window-laden ruin can no longer allow Infantry to hide away from vengeful Knights. The other rule here that’s familiar from 9th is around Movement – INFANTRY and BEAST units can move through the terrain feature freely, similar to the old Breachable and Scalable traits. These units (plus things with FLY) can also end their movement on upper floors, but only if their base (or hull) fully fits, and does not overhang the edge at all – no more precariously balanced tanks. If you climb up to a floor that’s at least 6” above the ground, you’re rewarded with an improvement of +1 to the AP of your shooting attacks against targets on ground level via the Plunging Fire rule.


Terrain looks functional enough, but is something we’ll probably need to see a bit more in action to tell if it’s really working. The wording around visibility is a bit finicky, but the actual outcome tends to make sense and be fairly simple to resolve, which is good. It’s also nice that there’s far more reason to put random pretty statues on the board than in previous editions and have them actually matter. We do think this would have been a good opportunity to codify the very common rule (including at GW’s own events) that ground floor windows block line of sight, perhaps as an optional additional keyword to add to features – though perhaps this was an intentional omission to allow Towering models more impact from the visibility changes.

We also think the switch to assessing area terrain effects based on models being wholly within is going to cause some hefty confusion as people adjust to it, and also invalidates some of the existing tournament terrain kits out there – the “medium” ruins used by the UKTC are designed on the basis that you can choose to “toe in” to the lip and see/be seen through the windows, but that no longer works based on these rules (and we’ll be interested to see how the UKTC adapts and/or house rules it, or if an early GW FAQ clarifies how this works for models partially in terrain). We’ve played a few test games with these rules, and there have certainly been some odd-feeling situations as a result of them that might require a rethink. Again, this feels like something that an optional keyword would be an ideal fix for!

Key Changes: Terrain and Cover

  • There’s only one kind of Cover, which is +1 to armour saves (unless you’re already on a 3+ or better against an AP0 attack).
  • Most terrain features provide Cover to any model that’s not fully visible to every model in an attacking unit.
  • Hills and Debris/Statues can now provide this, including to VEHICLES or MONSTERS.
  • Models are never fully visible when observed through a wood.
  • Ruins work like a combination of Obscuring and Breachable (SWARM models can no longer move through walls, however) terrain, and also provide Cover when models are partially visible because of them.
  • All area terrain effects now depend on you being wholly within them.

Objective Markers

A final key mechanic to look at before we move on to the phases of the game in part 2 is Objective Markers. Missions in 40K have often revolved around attempting to control Objective Markers, and 10th is no different in that regard. Good news – all those objective mats that everyone has ended up with over the course of 9th? Still valid. Objectives are still 40mm diameter circles, and objective control still requires you to be within 3” of them. While the markers themselves haven’t changed, though, how you control them has.

First up, units now have an Objective Control (OC) stat. A player only controls an objective if the total Objective Control of their models within range is greater than that of the opponent, otherwise it’s contested. The wording here is very carefully chosen – it means that if all of the models you have in range of an Objective have OC 0 (either because they come like that, or they’re Battle-shocked) then you cannot control it even if the opponent has no models there – both of your totals will be zero, so yours isn’t greater!

Objective Control both centralises a mechanic that was increasingly seen for large models in 9th Edition and replaces the Objective Secured ability that Troops had (and some other units could gain access to). This feels like a good change – it achieves both increased granularity and design space while reducing the number of edge cases and gotchas. In terms of design space, the biggest one is that Battle-shocked units have their Objective Control changed to 0, one of the key impacts of Morale. It also allows for other possible effects, such as those previewed for Dark Angels and Blood Angels. The former’s Grim Resolve Detachment ability allows their models to be OC1 rather than OC0 when Battle-shocked, which pairs nicely with the +1 OC from the Astartes Banner ability for Deathwing Knights; meanwhile the latter’s Death Company Intercessors are subject to the Black Rage and go down to OC 0 if there isn’t a nearby Chaplain to keep them focused. There’s just a lot more you can do with objective-control effects when they’re not as binary as “obsec” or “not obsec.”

A change here that we like much less is that you can no longer end a move on an objective marker (though can move through them freely). We can sort of see why this has been done, as one of the downsides of 8th and 9th edition’s objective systems is that cool, custom-modeled objective markers have almost completely disappeared from play in favour of the utility of mats. Unfortunately, while bringing those back is a laudable goal, there are a bunch of possible problematic interactions from objectives taking up space, and it feels like it risks doing one of the key things you don’t want in 40k – creating situations where a unit cannot do something that it obviously should be able to. It’ll be interesting to see if there’s more depth to how solid objectives will be used in the future, because at the moment this is one of the few areas where we feel like a change is causing more problems than it solves. That said, some of us certainly are looking forward to creating some cool objectives – did you know the Avatar of Khaine comes with two whole extra heads that would make awesome Aeldari shrines?

Key Changes: Objectives

  • Control of an objective is now determined via the Objective Control stat.
  • Your OC total within range of an objective has to be higher than your opponent’s to claim it, so models with OC 0 can never control an objective by themselves.
  • Units cannot end a move on top of an objective marker.

Next: Playing the Game

There’s a ton to cover here – 10th edition represents the biggest overhaul of the game since 8th, and although there’s enough familiar ground that existing players won’t feel lost, we think the end result should be a significantly different experience. The catch here is that quite a lot of the change is wrapped up in the datasheets, so exactly how different things are going to be will be heavily influenced by the quality of those.

In our next article we’ll cover playing the game, running through each phase and how those phases – and the rules in them – have changed. You can find that article here.

Have any questions or feedback? Are there changes you particularly like or hate? Drop us a note in the comments below or email us at