Space Marine Detachments

Earlier I wrote a quick walkthrough about army list selection in Warhammer 40,000 8th edition. Unfortunately, aspects of those rules demonstrate again that 8th edition is very good, but neither as slimmed down nor formal and clean as it has been hyped to be.

The issues crop up from the new incarnation of Objective Secured, which enables models selected as part of an army detachment with uniform faction to trump other models for control of objective markers.

Preview of Objective Secured rule from the upcoming Chapter Approved.

Copy & Paste

To begin, there isn’t really a rule for Objective Secured. There’s a rule for Objective Secured, Defenders of Humanity, Knights of Titan, and so on. All the different codexes are coming out with the same rule under different names, e.g., the Space Marines’ Defenders of Humanity. Meanwhile, to maintain some parity for the factions that don’t have a codex yet, GW previewed an Objective Secured rule to be included in the upcoming Chapter Approved supplement giving that ability to all of those armies.

This copying & pasting is strange and unfortunate. Defenders of Humanity made sense at first when the ability was initially presented to be a unique Space Marines advantage. The presumption was other codexes would then arrive with different but similar abilities. But it turned out they all just have the same ability. Note that the abilty per se isn’t the problem. Diversity of abilities would be interesting, but also harder to balance. It’s the presentation of this universal ability that is problematic. Even minor carve outs such as for Fabius Bile and Fallen being compatible with all the legions and thus not breaking the faction uniformity of Chaos Space Marine detachments don’t merit copy & pasting the entirety of the basic idea into each book.

To look at just one issue, because there’s no universal term, the rule concept can’t be expressed in as simple and formal a fashion as before. E.g., to paraphrase previously:

Models with Objective Secured trump models without Objective Secured for control of objective markers.

Instead the new rules have to be worded in terms of trumping models with “a similar ability” because they all have different names. What does “similar” mean? In practice it’s understandable, but it’s not as formal as it could be.

All this duplication under different names is unfortunate but a hallmark of this edition, a consequence of “streamlining” the game by eliminating common text from the core rules and main rulebook and instead pushing it out to numerous copies in the codexes and datasheets. If all the factions are going to have this rule, there should just be one straightforward universal rule. That centralization would reduce the overall volume of rules and text, foster understanding, be more formal, and prevent errors from creeping in over time with successive copying.

This is also another example of how GW went to all the trouble of introducing a keyword system, but isn’t actually using it well. Objective Secured could easily be handled more elegantly and formally by granting units keywords if their detachments meet given conditions and wording the ability around those keywords.


More critically, these rules contain ambiguities in their prerequisites. For example, Defenders of Humanity relies on the definition of a “Space Marine Detachment.” The other books are structured similarly. As explained below, that definition isn’t 100% unambiguous on whether or not a Space Marine Detachment can include multiple chapters within the codex, e.g., Salamanders and Ultramarines. It is explicit that Space Wolves and the other variant codexes are not included.

Beyond Defenders of Humanity, this ambiguity also raises rules questions about stratagems. Those listed in the codex are unlocked if you field a Space Marine Detachment. So must you field a detachment drawn from a single chapter to get access? Or would a detachment comprised of any mix of Space Marines suffice?

Mixed Chapters

In defining a Space Marine Detachment, the codex provides a list of chapter keywords which a “Space Marine unit” might have and then says:

A Space Marine Detachment is therefore one which only includes units with one of those keywords.

By far the most natural reading of this treats “with one of” as simply requiring each unit to have a faction keyword from that list, essentially grouping the last clause as:

… [units with one of those keywords].

The wording doesn’t actually make a binding to a single chapter keyword across the whole detachment, it permits a selection per unit. A detachment made up of Salamanders and Ultramarines would indeed quite obviously “only include units with one of those keywords.” Note that units can each only have one of the keywords in the given list, so “one” doesn’t instate any additional information as compared to, e.g., “any,” and is a more natural wording anyway for a selection of that type.

So in that straightforward reading, a detachment of mixed chapters would receive the benefit of Defenders of Humanity.

Single Chapters

Alternatively, a somewhat strained but plausible reading interprets “one of those keywords” as containing an additional stipulation that the units all share the same keyword from that list. It puts more meaning into the “one,” depending on how you look at it either adding an unstated “which must be the same for each unit” or grouping the last clause to the first clause:

A Space Marine Detachment is therefore one which only includes … one of those keywords.

In that case a Space Marine Detachment may only be comprised of “one of those keywords” and mixed chapters won’t receive the benefit of Defenders of Humanity.

A more complete definition under this reading would be, for example:

A Space Marine Detachment is therefore one which only includes units with one of those keywords, which must be the same for each unit.

Or, better:

A Space Marine Detachment is a detachment comprised solely of Adeptus Astartes units, all with the same <Chapter> faction keyword.

Intent & Practice

In trying to resolve that ambiguity, the intent is impossible to decipher from the text alone. Certainly it would be most traditional for a “Space Marine Detachment” to be comprised of a single chapter. However, it would also be quite reasonable and not at all out of line for Defenders of Humanity to apply to any mix of Space Marines. Chapter Tactics, which is explicit about being available only to uniform detachments, would then be an extra benefit for selecting units entirely from one chapter and strongly encourage that traditional makeup. The latter would be a more interesting structure and create somewhat more list building decisions, so it could easily be the intent.

In practice this ambiguity doesn’t matter much. The benefits of Chapter Tactics are so considerable and the ability to mix factions between detachments so flexible that there’s little reason to not field single chapter detachments. In theory though you might, e.g., if a future codex had weaker Chapter Tactics equivalents but strong characters from different chapter equivalents that you wanted to combine in one detachment but still be Objective Secured.

Next Level

As with the previous examples of textual (as opposed to mechanical) shortcomings in 8th edition’s rules, right now these generally aren’t actual problems due to the freshness of the duplicative copies and the competing interpretations of the ambiguity being obscured by the in-game strength of one. But they create openings for problems, particularly as the game evolves. With each new book there’s a chance to introduce a real error while pasting in its copy of Objective Secured. At some point there might be a real reason to field a detachment of mixed chapters/legions/dynastics/etc. and face real questions about what buffs it would receive.

The elimination of Universal Special Rules and other centralized concepts no doubt minimized the number of pages in the main rulebook. But it necessarily expanded the cloud of text replicated throughout all the books, with identical rules under formally and often even textually different symbols. Objective Secured and all its variants such as Defenders of Humanity are a prime example. That unnecessary inelegance and volume of text is unfortunate, a product of over-minimizing and false simplification.

The ambiguity in defining Space Marine Detachments isn’t hard to see and the definition trivial to improve. So it highlights that although much improved, Games Workshop’s ongoing reviews of 40k material are still very limited and non-technical. The playtest group is still too small, coming in with too many shared assumptions, not analyzing the language or mechanics formally enough, and sharing too much extra-textual context and intent to catch all possible interpretations and other potential issues. It is a much longer discussion for another day, but for a such a complex technical system (the game) and with such a large, diverse, and disconnected audience implementing that system (players worldwide), large scale public review is strongly warranted. That could be done in an efficient fashion to minimize burden on GW’s end, and, as other games as well as GW’s own recent public rules releases (for both 40k and Age of Sigmar) have demonstrated, in such a fashion that it wouldn’t hurt sales.

To take 40k to the next level of elegance and excellence, the design process should:

  • Focus streamlining on minimizing overall rules volume and duplication, rather than superficial main rulebook page count reduction;
  • Continue to expand the scope, diversity, and extent of peer and public review.

40k 8th edition is very good. But it could be even better with minimal effort and cost.

Battle Hex

Going through my folders and deleting a bunch of old stuff. Wanted to post this up for posterity. Draft for a series of tiles to get printed on heavy cardstock, used in various miniatures games (with and without hex grids). Later this would have been a great Kickstarter project, but at the time there wasn’t any great way to build up a market and confidently order enough to make the price reasonable. These days I don’t do enough drawing and graphics work to crank these out.

Derelict Depot

Battle breaks out amid the newly completed Derelict Depot!

Advancing through the wreckage.

Looking out from the abandoned garage.

Lurking in the shadows.

Moving through the scrapyard.

Garrisoning the mechanical building.

Scouting for trouble.

Overlooking the battle.

Showdown at the depot nexus!

Derelict Depot

The Derelict Depot is a board I put together for RECON+, essentially half-size games of Infinity, but it should work for a variety of skirmish games. It’s a mix of scratchbuilding, scale models, and 3D printing. More details on its creation are here:

I designed all of the 3D printed parts. Many of them are already available as free downloads in my Thingiverse collection.

The armies fighting it out here are my Military Orders and Aleph painted by Tim D.

The first step: Putting down some initial ideas.

3D printed and scratchbuilt elements.

Construction complete!

Base coating.

Painting details.

The final board!


The story of this terrain is something like:

Early in the colonization of Ariadna, Depot E-7 was a supply outpost used by militias fighting the antipodes on the fringe of the settled area. As the border expanded outward and it was no longer militarily useful, a bold, risk-taking entrepreneur began using it as a base for an air courier service. Given the harsh conditions, limited technology, and few resources available to the colonists, its equipment was all based on very old and simple technology easy to construct and maintain. The service provided an important link ferrying supplies, messages, and people over the dangerous ground between the new, far flung settlements popping up as the colony grew rapidly. Later though the depot was overrun as its region collapsed in one of the periodic waves of antipode fighting. Although abandoned since then, it has recently come to be occasionally used as a waypoint or temporary base by various special forces teams operating on Ariadna.

The board is of course designed overall to feel abandoned and disused, but particulars of that story are captured in details here and there: Signage declares the garage to be the home of the “Air Bonsky” courier service (Bonsky being our local lead Infinity TO); militia recruitment and “EVACUATION NOTICE” posters are scattered about on some of the walls and littered on the floor; blood spatters mark where the last defender was caught when the base was overrun; a walkway has been twisted and burnt by high explosives in more recent fighting. It’s not much of a story, but it was just enough to generate some unique, cohesive imagined micro-vignettes and details to add flavor.

Air Bonsky: Why fight the antipodes when you can fly over them?

Evacuation notice poster on a wall.

Littered recruitment poster and evac notice handbill blown into a corner.

A warning not finished in time.


This board is definitely designed with just a bit of priority toward aesthetics and narrative versus gameplay. In a few places it can be a touch awkward to place figures because of details, many of the shapes are slightly odd so models often don’t perfectly snug up into cover, and so on. But it’s very playable, and has interesting features.

As one example, none of the buildings have the ubiquitous low walls found on almost all Infinity MDF terrain. In places where railings make real-world sense and cover would be useful for gameplay, the metalwork is more realistically thin and open, but overgrown in thick vegetation to physically obscure models and leave no doubt they’re intended to be cover. In other places, a variety of mechanical boxes, large vent outlets, and other details scattered about provide partial cover instead of walls and screens. This approach creates some interesting dynamics. For example, the top of the garage can be a great vantage point for controlling ground below. But it’s essentially not possible to move around on it without either breaking cover between features or going prone out of sight and foregoing your own shooting, quite different from moving along a rooftop railing or edge. At the same time, it’s not possible to get cover from all angles, so no sniper can rest easy if there’s a chance the enemy can flank them—which they might very well do by running through the garage directly underneath them!

Similarly, the tallest point, the silo, has a piece on top such that models can generally only be placed solidly at the very center. A small lip prevents models from fitting at the edge. So a sniper can be placed there for a commanding view, but if they go prone they won’t be able to shoot anything, and if they stand up they won’t get cover.

The board as shown here is very dense, which impacts some armies negatively, but that just means there’s plenty of pieces to be used or not used in different games, generating a lot of variety in potential setups.

Face-on view.

Mechanical building side.

Fuel reservoirs side.

Top view.

Sniper hiding behind a rooftop mechanical box.

Roof of the garage.

Poster inside the garage.

One of Bonsky’s relic aircraft.

The mechanical building.

Gas mask warning and ladder on a fuel reservoir.

Burnt out low-tech car.

Fuel distribution tank.

Creeping behind the distribution tank.

Truck dumped out front the distribution tank.

A silo, the tallest point on the board.

Door on the silo and truck left outside.


I’m very happy with how the Derelict Depot came together. It was a nice, tractable effort that didn’t drag on forever, and got done on schedule—just barely!—for an event I wanted to use it in. My small library of 3D printable parts made expressly to quickly add details to scratchbuilt terrain like this provided plenty of variety and interesting features, and I enjoyed making good use of a number of found objects. People seem to enjoy playing on the board, the pieces have some neat game dynamics, and the terrain has a lot of character and cool visuals. Mission accomplished!

For another example of this kind of scratchbuilding + scale models + 3D printing, check out my Medea Refinery build. Partly by chance and partly by design, pieces from the two sets go together well to create a really cool, large, detailed board. I also have a few tutorials up on 3D printing and modeling.

I’m not sure quite when I’ll get to them with NOVA and other events coming up, but I’m kicking around a couple neat ideas for new boards and in some cases have even started some work. Stay tuned!

As a bonus, the Derelict Depot packs up perfectly into a box I had on hand!