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Back In The Future, a Review of The Horus Heresy: Betrayal at Calth from Games Workshop

Games Workshop has a brand new stand-alone board game available. It takes place during the tumultuous times of the Horus Heresy, when the various Space Marine chapters split apart, some of them staying with the Emperor, and others following Horus and converting to the powers of Chaos. The wars that would rage on from this split will last at least 10 millennia. One of the biggest events in the Heresy was the Betrayal at Calth when the Ultramarines fought the Word Bearers. The Betrayal at Calth box set lets you play out those claustrophobic battles in the tunnels beneath the planet’s surface.


Games Workshop has been kind enough to send me a copy. I did an unboxing of it last week. Now I’ve had a chance to play the game some and it’s time to give you a look at how it works. So grab your bolter. It’s time for another TGN Review. This time it’s Betrayal at Calth.

An Introduction to my Past:

Warhammer 40k was my original miniatures game I got into the hobby with. I started in 2nd edition and played right up until 4th. I still have some of my Orks, in a tackle box sitting in my living room. So yeah, I’ve got quite a history with the setting. And while I never was one to delve much into the fluff for the universe, I certainly knew what the Horus Heresy was. It’d be impossible not to know about it in at least passing while you play the game. And certainly I’d seen all the different armor styles that the Space Marines have worn over the years.

Along with 40k, I’d played my fair share of games of Space Hulk. In fact, one of my first purchases for 40k was splitting a Space Hulk set with my friend. I got the genestealers and he got the marines, since those were the factions we played at the time. Of course, we played plenty of games of Space Hulk, itself, when we’d get together and didn’t want to play 40k. So, with my history with the two games, I was rather excited to get a chance to try Betrayal at Calth.

Seeing as I already did an unboxing article about the set, I’ll leave the majority of discussion about the components left un-repeated here. Instead, I’ll just focus on the gameplay, itself. The one thing I will mention is that I figured I’d get a lot of extra bits, but I was basically overwhelmed with the choices on those sprues. In the scenarios, there’s no specific way they say to arm your figures, so GW gave you all the potential options in modelling. It was actually a bit daunting at the beginning, trying to decide how I wanted each of the squads armed. This led to several hours of “analysis paralysis.” Thankfully, I eventually remembered that I had magnet kits.

When I initially was looking through the set, I was making mental comparisons to Space Hulk more than I was to 40k. And really, having read through the rules and played the game, it plays a lot closer to the former than the latter. You’re not going to have the traditional forms of squads and attacks like you do in 40k. In fact, throw out your traditional definition of “units,” as that’ll only confuse you moving forward. But I’m getting a bit ahead of myself.

The Status of Stats:

In the game, you play as either the Ultramarines or the Word Bearers. Each force has certain models that they can take, depending on what scenario you choose to play. The model’s stats are on the oversize Reference Cards. Looking at a card, we see the stats for:


Armor: This is how many dice you roll when hit by an attack. For each Shield you roll, you remove a Hit.

Stamina: This is how much damage a model can take before it is removed. However, it’s not a “wounds” system. It’s a threshold. So you don’t have to track wounds as a model moves around. More on how this works in the full attack section later on.

Assault: This is how many dice you roll when making a melee attack.

Bulk: This is either 1, 2, or 3. A hex can have a maximum of 3 Bulk worth of models in it at a time. Regular Marines are 1. Terminators are 2. The dreadnaught is 3. Yes, this means you can have a Terminator and a Marine in the same hex (and they count as a unit. Told you to throw out your traditional thoughts on that term).

Below the stat block are any special abilities that model type has.

The one thing you’ll notice is that the Reference Cards don’t have weapons listed on them. That’s because, as I mentioned above, GW gives you all the options for building your figures, but doesn’t specify what type of armaments you need for a particular scenario. That’s up to you. As such, all the stats for the various weapons (ranged and melee) are in the rulebook (and they put an extremely handy Quick Reference Guide” on the back of the rulebook). Obviously, each has their own advantages. Lightning Claws give you lots of extra dice in Assault. Meltaguns treat the first target hit as having Armor 0. Flamers can potentially attack multiple hexes if they get a Critical result. Missile Launchers potentially let you add extra dice to the attack roll depending on how many models are in the target hex. And on and on. Depending on what bonuses you feel outweigh others, you should arm your figures accordingly.

The Reference Cards for the two special characters in the game are double-sided. They represent a regular and Wounded version of the characters. Make sure to always start with the regular side up when playing. The first time these characters would be removed from the game, instead flip their card over to the Wounded side.

Location, Location, Location:

Turning from the models to the board, itself, we see that it’s broken up in to various pieces. They vary in the number of individual hexes on them and can be arranged in many different ways. Each scenario has a specific way that you arrange the tiles to form the game surface. There’s three types of hexes: open, blocked, and rubble. Open hexes are just that. Models can move around in them or shoot through them with no penalty. Blocked hexes are the exact opposite. You can’t move into them and they block line of sight for shooting. They have a red outline. Rubble hexes are in the middle. They have some detritus in them, but they can still be moved into. When making a defense roll while in a rubble hex, you get to add an extra die. Rubble hexes have a white, dotted outline. There are also removable obstacle/obstruction markers, as well as sealed/open blast door markers. The specific scenario will tell you where these are placed on the board at the start of the game.


Besides the board and minis, there are various other components that go into the game. Let’s take a look at how they work.

Command Cards: These are special cards that give you some sort of bonus during the game. Each card specifies how it works and when it can be played.

The Dice: The dice for Betrayal at Calth are custom to the game. They are 6-sided, but have faces with various other symbols on them. There’s one side that’s blank, two sides marked as “hits” (the two concentric circles), one side marked as a critical hit (the side with the skull), and two sides marked with shields (the triple-diamond shape).

Tactical Markers: These are double-sided with two icons on one side and one icon on the other. These indicate how many Tactical points a Unit has. These work like Actions in other games. Basically, a unit has two actions they get during a turn. When they use one, they flip from the 2-icon side to the 1-icon side. Then when they use their second, you simply remove the token.

Get on with it!:

So that’s all the components and such, let’s actually get into the nuts and bolts of playing the game.

Setting up a game starts with picking a scenario. There are six in the book that make up a short campaign, though, currently, there’s no sort of “if you do this in Scenario 1, then you get this in Scenario 2” sort of mechanic. So you could play any scenario you want, as you don’t have to go in order.

The scenario will tell you what forces are available to you to choose from, how the board is set up, how many Command Cards you start with in your hand, and how many you put into your Command Deck. It will also explain the win conditions for the scenario. None of them are simply “kill off the other player’s models.” While there are certainly ones where killing off a specific model will be a win condition, it’s not always the case. So pay attention to those special rules, or you might find yourself losing when you didn’t expect it.


The game is played over a series of rounds. Each round consists of three phases. They are: Initiative Phase, Ready Phase, and Action Phase.

In the Initiative Phase, both players roll three dice. The player who rolls more Hits gains the Initiative and will activate first in the Action Phase. Reroll in case of a draw. Also, in some cases, the scenario will say a specific side has Initiative for the First Round of the game.

In the Ready Phase, both players draw a card from their Command Deck into their hand and they give all of their Units 2 Command Points.

Then there’s the Action Phase. This is where things really happen in the game. Starting with the player who has Initiative that round, players take turns activating units. A unit is any group of models in a hex. So that can be just a single model, or up to three marines at a time. The models don’t have to be of the same type. So if you have a Terminator and a regular Marine in the same hex, they are a unit and will activate together.


Lights, Camera, Activation:

When you activate a unit, you have several options for what sort of action they will do. The options are: Advance, Run, Consolidate, Assault, and Shoot. An overview of each:

Advance: Move the unit 1 hex in any direction. They cannot move onto an occupied hex (so no, not even a hex with friendly models in it, even if there’s room. You’ll see why in a minute).
Run: Move the unit 2 hexes in any direction. Like above, they can only move through unoccupied hexes.

Consolidate: This is why the above two require you to not go into unoccupied hexes. Using this action, you can have models join/leave units. Models in a hex can move up to one hex away and can become part of new units. Each model in a hex can exit to any adjacent hex (as long as there aren’t any enemies in it). So you can have a unit split up, or just have one guy move to a new unit. When joining a new unit, that unit retains the same number of Tactical Markers. So having some new guy jump in with them doesn’t suddenly tire them out. Though it does create a situation where a model could piggy-back his way across the board, joining adjacent units and still being able to activate later on, but it’s fairly rare that such a thing happens, and requires a whole bunch of extra set-up to accomplish.

Assault: The unit may make a melee attack roll against an adjacent enemy unit. If the activated unit isn’t currently next to an enemy unit, they may move up to one hex (unoccupied only, of course) before making the attack.

Shoot: The unit may make a ranged attack against an enemy unit within range and line of sight. Line of sight is found by tracing a line from the center of the firing unit’s hex to the center of the target’s hex. If this line doesn’t pass over other any sort of obstruction, there is clear line of sight. If the direct line is blocked so you can only draw a line from the center of the firing unit’s hex to only a part of the target hex, then it’s an obstructed shot and the defending unit will get bonus defense dice. Bonus defense dice also come into play if the target is in a hex with rubble in it.

Note: When a unit is adjacent to an enemy unit, it is considered “Pinned.” When Pinned, a unit can only Advance, Consolidate, or Assault when it activates.

So you’ve got your weapons set. You’ve got your enemy in your sights. It’s time to deal some hurt. How do attacks in the game work? Well, first, you designate the enemy unit you’re attacking. For melee attacks, they have to be adjacent to you. For ranged attacks, they have to be within range of your weapons (each one is different and will list how many hexes away they can target). You count up all the dice allowed by the unit making the attack. Each weapon has a certain number of dice it adds to the pool of dice you get to roll. It doesn’t matter what type of weapon it is, you collect them all together. You then roll your dice and count up the total number of hits. If any of the dice roll a Critical, you pick one weapon out of the group you used and apply its Critical Effect (and, of course, a Critical counts as a hit, too). Once you’ve totaled your hits and decided on your Critical (if any), the player making the attack designates a specific model in the enemy unit to be the first model hit.

The defending player then grabs dice equal to the model’s Armor stat (plus any bonus dice from terrain or other effect) and rolls them. For each Shield rolled, that negates one Hit. Then, compare how many Hits are left versus the target model’s Stamina. If the number of hits is equal to the model’s Stamina, it is removed as a casualty. If, after you remove the model, there are still hits left over, the attacking player picks another target in the enemy unit (if there are any left) and once more a Defense roll is made, once more discarding hits equal to the number of shields rolled, and comparing remaining hits to the Stamina of that model. Lather, rinse, repeat until there aren’t any enough hits to beat a target model’s Stamina.


If you were attacking with an Assault Action, if there are enemy models still present after the attack resolves, they get a chance to attack back with whatever figures are still alive. This attack back works exactly like the original attack, but just with the combatants reversed. Once both sets of attacks are resolved, count the number of models removed from each Unit involved. The Unit that lost more immediately makes a Consolidate action (for free) and must leave their hex into another hex that’s not adjacent to an enemy model. If they can’t do that, they make a Desperate Last Stand roll. The player controlling that model rolls a die. On a Shield, that model stays where it is (but loses any Tactical points it had). If they roll anything else, the model is removed as a casualty. It’s dangerous in those dark, claustrophobic corridors.

I should note that damaging the Dreadnaught is a little different. With a Bulk of 3, it will always be the only model in any given hex. Instead of picking a target model within the hex, the defending player shuffles the location cards for the dreadnaught and draws one at random. That’s where the shot lands. Each location has its own Armor and Stamina values. If a location is destroyed, the card will tell you what effect that has on the dreadnaught.


So… there you have it. You’ve got your model descriptions. You’ve got your scenarios. You’ve got your activations. You’ve got your attacks. You’re ready to go play some Betrayal at Calth.

Thoughts and Look to the Future:

I rather like the game. As I mentioned, it reminds me a lot of Space Hulk, what with the cramped, close quarters, and how most of the time you start almost right up on top of one-another. The dice mechanic for attacks is quick and easy and you don’t have to look through any sort of charts on “well, this weapon has strength X and you’re toughness Y” or anything like that. It’s meant to feel more like a tactical board game than a miniatures war game or even a miniatures skirmish game and I think it does that well.

Games Workshop has announced that they're bringing back their Specialist Games Division. While some people are concerned that it's just a "Cash-grab" or that it's "too little, too late," I'm being a bit more optimistic about it. The Betrayal at Calth could be seen as the first offering on a company that's looking to branch out from just their core two products and give gamers what they want. If future sets stand up to the standards I see set here, I'm super-excited about what will be coming out in the future from the company.

So if you want, go pick up a copy of Betrayal at Calth from the GW Webshop or your LGS.