Ruleshammer 40k: Engagement Range and Obscuring Area Terrain

Welcome to Ruleshammer! This week I’m covering some of the odd interactions made possible by the latest FAQ for Obscuring Terrain. Remember the banner below will take you to the Ruleshammer 9th Edition Compedium, for all the questions I’ve answered for the last few months!

This FAQ rule was removed on 12th September 2022. This article will remain to list the many reasons that might have contributed to it’s deletion.

The latest FAQ included a change that has been a long time coming in warhammer 40k; a change to remove one of the games most divisive interactions between models and terrain. It did so with a pretty significant addition to perhaps an odd choice of terrain rule. I thought this week I would diagram some examples of this change in action, some of things it does right and some of the consequences that might not have been intended.

Here’s the change:

‘While a model is within 1″ of an Area Terrain feature with this trait (e.g. Ruins) and the shortest line between it and an enemy model crosses over or through this terrain feature, then while those models are within 2″ horizontally and 5″ vertically of each other, they are within Engagement Range of each other.’

Lets go through a few examples, starting with what was quite clearly the intent.

The Main Thing – Preventing Charge Blocking

Rob: One common technique you’d see employed in competitive play was to place models just at or under 1″ back from the wall of a ruin. At this point, the distance from your models to the wall, when combined with the width of the wall, gives a distance more than 1″, preventing enemy models from being able to reach your models in engagement range while they are on the other side of the wall. At the same time, a model on a 32mm base can’t fit into the gap on the other side of the wall between your models and the wall, and can’t end up inside the wall either, effectively preventing them from charging your unit unless they go around or move up to an upper floor that puts them in engagement range instead. I’ll throw it back to Vre’kais to illustrate:

Rob: Note that this doesn’t actually prevent blocking charges through ruin walls, it just does so for models on 32mm or smaller bases – you can still set up just under 2″ back in a ruin and prevent models on larger bases (50mm+) from tagging you through the wall.

Using Consolidation to End up Outside Engagement Range

One consequence of this is that moving out of a ruin can, in certain circumstances, “turn off” the increased Engagement Range, allowing a unit to move out of Engagement Range when consolidating or piling in, even while moving closer to the nearest enemy model.

Note: While the terrain is still between the rear Marine and the Horrors the check for this rule is the “shortest line between it and an enemy model”.

Impacts on the Effectiveness of Screening

This can also make screening more difficult, and generally you’ll need to space things out more to prevent charges in ruins.

Cut Them Down Range Increase

8″ Charges from Deepstrike

Rob: Those odds further increase if you have the ability to give your unit +1 to charge distances, such as with an ability like Abaddon’s aura or the World Eaters’ Violent Urgency Warlord Trait.

Movement Blocking with Close Terrain

Note: This was of course possible with normal engagement range but doubling the area that models can cover makes it far easier to do with a small number of models.

Movement Blocking between Obscuring Terrain

There are also some unexpected impacts this has on moving between occupied Obscuring Terrain pieces with large none FLYing models.


This is by no means an exhaustive list of the ways this change can have unexpected consequences but it’s some of the more reproducible situations that might come up naturally without too much effort.

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