Ruins and the benefit of cover is one of the most misunderstood aspects of Warhammer 40K in 10th Edition. When does a unit get cover from a ruin? Who benefits from cover? How is visibility determined in regards to ruins? These are questions many newcomers face in their games of Warhammer 40K. In today’s article I’m going to break down ruins in Warhammer 40K and explain how visibility, movement and the benefit of cover works.
Why specifically focus on ruins terrain as opposed to others? Because most Warhammer 40K competitive events only use ruins terrain pieces. Craters, woods, barricades and more are great pieces to use in your thematic and narrative battles, however when it comes to tournament Warhammer 40K, ruins are the sole terrain pieces used. With that said, let’s get into it!
How Ruins and Benefit of Cover Work in 10th Edition Warhammer 40K
First off let’s take a look at the Warhammer 40K Core Rules for ruins:
Ok that seems pretty straightforward…but wait…there’s more. These rules have been refined and “updated” with key errata in the Core Rules Update and Designer’s Commentary. Let’s take a look at these revised sections:
So, we see there is some changes in the Movement and Visibility sections of the Core Rules for ruins. The most notable change here is that Imperium Primarch and Belisarius Cawl can move through ruin walls along with Infantry and Beast keyword units.
In the Visibility section we note the change from the original rules removing Towering models from being unprotected by intervening terrain and further only having to be “within” as opposed to “wholly within” to “see out of it normally.”
The Benefit of Cover section clarifies that a model can gain the Benefit of Cover in a ruin if it is “wholly within” the terrain piece OR if the model is not fully visible from the attacking model due to the terrain piece.
Sounds confusing right? No fear, dear reader, just follow me and I shall make all clear.
Movement in Ruins in Warhammer 40K
Now, we have noted above that there are certain movement limitations in ruins terrain pieces. Infantry, Beasts, Imperium Primarchs, and Belisarius Cawl models can move through the walls of ruin terrain pieces freely regardless of the height of the ruin. Other models such as Vehicles, Monsters, and Mounted units etc cannot move through these terrain sections, BUT that only matters if the terrain piece is greater than 2″. Let’s look at the Movement section in the Core Rules.
This is important, especially in competitive Warhammer 40K events, because some sections of a ruins terrain piece will be considered 2″ or less in height. So a small ruin wall section that is designated as 2″ or less CAN be moved through by ANY model (it just cannot end it’s move ON the ruin wall). Let’s look at this in practice.
In the picture above we have an Impulsor which has the Vehicle keyword behind a ruin piece. The ruin piece here is 2″ or less so the Impulsor can move through it as long as it can end it’s move on the other side of the wall.
Here we see the Impulsor after moving through the 2″ wall and ending with its movement on the other side. Because the terrain feature is 2″ or less, it does not impede the Impulsor’s movement despite it having the Vehicle keyword.
Now let’s look at how Infantry units move through walls.
This squad of Intercessors is behind the ruin wall, but despite that wall being greater than 2″ they can move freely through the wall so long as they can end their movement on the other side of the wall.
The Intercessors move through the wall ending on the other side of it after making their 6″ movement. Because they are Infantry models they are able to move through the wall of the ruin unimpeded by the terrain.
These are the very basics of how movement works in ruins terrain in Warhammer 40K games. In summary:
- Infantry, Beast, Imperium Primarchs, and Belisarius Cawl models can move through ruin terrain walls freely regardless of the height of the ruin.
- All other models can only move through a ruin terrain section if that piece is 2″ or less in height.
- Regardless no model can end its move on top of or within a ruin terrain wall section
Visibility in Ruins in Warhammer 40K
While movement is pretty simple to understand, visibility becomes a bit more complicated. It is important to understand the distinction between “within” and “wholly within” as both of these define how models interact in terms of visibility.
A model is “within” a ruins terrain piece if any part of its base or hull (if it doesn’t have a base) is touching the ruin or its footprint.
A model is “wholly within” if every part of its base or hull (if it doesn’t have a base) is entirely within the footprint of a ruin.
Why is this distinction important? Because if a model is “within” a ruins terrain piece then visibility can be drawn to it however in order for a model to draw line of sight outside of a ruin it must be “wholly within” (unless it is Towering…we’ll get to that in a bit).
What does this mean? It means that a model can potentially be visible to enemy units, and thus be targeted by ranged attacks, while being unable to make ranged attacks themselves. Let’s take a look at this in practice.
In the example above we have a unit of Intercessors within a ruin terrain piece. Four of the models are “wholly within” the terrain piece and thus can fire at the Rangers as they can see outside of the terrain piece. The fifth Intercessor cannot make ranged attacks against the squad of Rangers as the model is not “wholly within” the terrain piece and thus cannot fire out of it to a target on the other side.
Conversely, the Rangers can draw visibility to ALL models in the Intercessors unit because all of the models in the unit are “within” the ruin terrain feature and are therefore visible.
Now, let’s look at this from a different perspective.
In this example, the Intercessors can ALL make ranged attacks. Despite the one Intercessor model being only “within” the terrain, it can draw line of sight to the Rangers without passing through the ruin terrain piece. Thus it can make ranged attacks against the enemy unit. Conversely, the Rangers can also still make ranged attacks against the Intercessors as they are “within” the ruin and thus visible to them.
Let’s look at how this works with Vehicle models.
In the above example the Vindicator is “within” the ruin terrain piece, however because it is not “wholly within” the terrain footprint it cannot make ranged attacks against the Wave Serpent. This is because it cannot draw line of sight to the Wave Serpent without going through the ruins terrain piece. It can, however, make ranged attacks against the Swooping Hawks unit as it can draw line of sight to them without going through the terrain piece.
Conversely the Wave Serpent can make ranged attacks against the Vindicator as it is “within” the ruins terrain piece and is thus visible to it.
Now let’s look at this with the Vindicator “wholly within” the ruin terrain piece footprint. Because it is wholly within it can “see outside of it normally.” Meaning as long as there is not another intervening piece of terrain, it can make ranged attacks outside of the ruin. This means it can declare ranged attacks against the Wave Serpent as well as the Swooping Hawks and, of course, those units can also make ranged attacks at the Vindicator as well.
Remember how we mentioned Towering models earlier? Let’s take a look at how Towering models interact in a similar scenario.
Towering models and visibility work differently than other models. Take the Imperial Knight Crusader pictured above. It has the Towering keyword which means it only needs to be “within” the ruin terrain feature to “see out of it normally.” This means that it can simply “toe in” to a ruin piece and still shoot outside of that terrain feature. Thus it can make ranged attacks against the Wave Serpent and the Swooping Hawks in the example above. It does not need to be “wholly within” to shoot out of it. Of course, because it is “within” the ruin terrain piece it is also visible to the Wave Serpent and Swooping Hawks.
So now that we’ve demonstrated how visibility works for models both “within” and “wholly within” a ruins terrain feature, let’s take a look at how terrain works for drawing visibility to models NOT within the terrain feature.
Let’s take a look at the first line of the Visibility section again which says:
“Models cannot see through or over this terrain feature (i.e. a unit outside this terrain feature cannot draw line of sight to a target on the other side of it, even if it would be possible to draw line of sight to that target through open doors, windows, etc)”
In the example above, the Vindicator is behind the ruin feature and, despite there being a clear opening in the terrain, the Wave Serpent cannot draw line of sight to it because it cannot do so without passing through the ruin terrain feature. Since the Vindicator is not “within” the ruin terrain feature, it is not visible to the Wave Serpent. The Vindicator also cannot draw line of sight to the Wave Serpent for the same reason. In the picture above, four of the Swooping Hawks can draw line of sight to the Vindicator because they can do so without passing through the terrain feature. The fifth Swooping Hawk, however, cannot draw line of sight to the Vindicator without passing through the terrain feature and thus cannot target it with ranged attacks.
These are basic examples, however common interactions you will see in your games of Warhammer 40K when it comes to ruins and visibility.
Benefit of Cover in Ruins in Warhammer 40K
This is probably one of the most debated aspects of Warhammer 40K in 10th edition. We know that the Benefit of Cover granted by a terrain feature (or a special ability) gives the target +1 to its armor saving throw, but let’s take a look at the actual Benefit of Cover rule:
Now it’s important to note that a Model with a Save characteristic of 3+ or better cannot have the Benefit of Cover against attacks made with an Armor Penetration of 0. In other words, if you have a base Save characteristic of 3+ your armor saving throw can never be lowered to a 2+ save because of cover. Also note, that cover can never modify a model’s Invulnerable Save as it applies only to a model’s “saving throw.”
Now, that we have covered that let’s move on to how this applies to ruins terrain features in Warhammer 40K. The rules for ruins and the Benefit of Cover are as follows:
“Each time a ranged attack is allocated to a model, if that model is either wholly within this terrain feature, OR it is not fully visible to every model in the attacking unit because of this terrain feature, that model has the Benefit of Cover against that attack.”
This is a pretty basic example of how the Benefit of Cover works in ruins terrain in Warhammer 40K. In the example above, the Intercessors are all “wholly within” the ruin terrain feature. This means that all the models in that unit will have the Benefit of Cover because they are all “wholly within” it. So, they would receive +1 to any armor saving throws made against attacks with AP -1 or greater.
The Wave Serpent has a Twin Bright Lance attack that is AP -3. This means that the Intercessors, whose base Save characteristic is a 3+ would receive a +1 bonus to their armor saving throw against the attack. Meaning that instead of needing a 6+ to save against the Wave Serpents Twin Bright Lance, they would save on an armor saving throw roll of 5+ against the attack.
The Swooping Hawks all have guns that are AP 0. This means that, despite having the Benefit of Cover against the Swooping Hawks ranged attacks, the Intercessors cannot modify their armor save characteristic beyond their base 3+ Save characteristic. So they would still have a 3+ to saving throws made from ranged attacks by the Swooping Hawks. The Intercessors still have cover because they are wholly within the ruin, but cannot benefit from the +1 to their armor saving throw because the attacks are all AP 0.
Now, let’s look at some more trickier examples of this.
In this example, the Striking Scorpions are all equipped with AP -1 Shuriken Pistols. Two of the Intercessors are wholly within the ruin terrain feature, while three of the Intercessors are not and are fully visible to all the models in the Striking Scorpions unit. This means that when the ranged attacks from the Striking Scorpions are allocated to the Intercessors, the only models in the unit that will gain the Benefit of Cover are the two that are “wholly within” the ruin terrain feature here. Because the AP of the attack is -1 those models can gain the Benefit of Cover against those attacks (making their armor saving throw a 3+ to succeed), however once they are destroyed, further attacks allocated to the three Intercessors outside of the ruin terrain feature would not have the Benefit of Cover.
Now let’s see how this works with Vehicle and Monster units.
Now, this is where ruins and the Benefit of Cover can get a bit tricky and confusing. Remember that if a model is “wholly within” a ruin terrain feature OR is not “fully visible” to every model in the attacking unit because of this terrain feature, that model can gain the Benefit of Cover from the ruin.
In the example above, the Death Company Dreadnought is “within” the ruin terrain feature, meaning it is “visible” to units outside of the terrain feature. In this example, three of the Fire Dragons can draw full visibility to the Death Company Dreadnought, while two cannot draw full visibility because of the ruin wall partially blocking line of sight. Even though the Death Company Dreadnought is not “wholly within” this terrain feature, it still gains the Benefit of Cover from ALL of the Fire Dragon’s ranged attacks because it is not fully visible to EVERY model in the attacking unit.
As you can see, this can get quite confusing on the table determining which models have the Benefit of Cover, when it is applied and how. It also gives a pretty big advantage to single model units, like Vehicles and Monsters. Even if only one model in an attacking unit containing multiple models cannot draw full visibility to the lone target model, that target model will receive the Benefit of Cover from the ruin against all of the attacking unit’s ranged attacks.
Final Thoughts
Ruins and the Benefit of Cover in Warhammer 40K games can be a bit confusing especially to newer players. It is important to understand how various units move within ruin terrain features, how visibility is determined both into and out of a ruin terrain feature and how the Benefit of Cover is applied. These are some basic examples that can give you a better example of how to understand how ruins work in your Warhammer 40K games.
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