The new edition of the Horus Heresy is here, and there’s no better time to dive into playing the terrible battles of this dark age. With a full rules revamp, a new starter set and a plethora of army books all dropping at launch, we’re diving in to give you our first impressions of the new edition, hitting the highlights of what’s new, what’s interesting and what’s worth playing in third edition Heresy.
Before we get started, thanks to Games Workshop for sending these over for review.
Not even at the man release of third edition yet and we already have our first expansion! This new campaign Journal covers the Istvaan V Dropsite Massacre that the Saturnine box is themed around, and per the title is apparently the first of multiple Journals that will release on this topic. It is one of the biggest events in the whole Heresy after all. This Journal covers the story of the initial and most vicious fighting of the Dropsite Massacre with as much or possibly more detail than the lauded Black Books did, as well as a new Legendary Mission, rules for Battlefield Assets, a couple of new units for the Legions Astartes, and a new Auxiliary Detachment.

Lore – The Urgall Depression and Dropsite Massacre
For those unfamiliar, the The Istvaan V Dropsite Massacre is the true beginning of the Horus Heresy wherein Horus springs his first real trap against the Loyalist forces and aims to make a clear a route to Terra by nullifying all of his enemies at a stroke. Unbeknownst to the Retribution Fleet sent by Rogal Dorn, 4 of the 7 legions sent to crush Horus’ rebellion had already pledged themselves to his cause; the Iron Warriors, the Night Lords, the Word Bearers, and the Alpha Legion. At this point in the story, the Thousand Sons had not yet turned traitor, Horus believing Magnus to be one of his biggest threats and attempting to manipulate Leman Russ into disposing of him at the Burning of Prospero. The book also briefly covers the demonic trap Horus set for the Blood Angels at the Signus system and the far flung “busywork” pacification he sent the Dark Angels, getting both Sanguinius and the Lion out of his way.
Once the Loyalist forces on Istvaan V had committed to an offensive in the Urgall Depression, a natural valley and killbox engineered by Horus at the foot of a giant volcano, the Traitors sprung their trap, surrounding and slaughtering the Iron Hands, Salamanders, and Raven Guard. The Journal takes a piece by piece look at this conflict, adding to the extensive lore already in place from the Forge World Black Books and the numerous Black Library novels covering this event (Flight of the Eisenstein, Fulgrim, Deliverance Lost, and First Heretic to name a few.) This section is worth reading even for long time Horus Heresy fans, as even I, someone immersed in the lore of the Horus Heresy for over 15 years, still had bits that I was able to pick up. Despite this event being covered by the Black Books and Black Library novels, it is a critical event in the chronology of the Heresy that hasn’t been covered in any meaningful way in almost a decade. This Journal is a great starting point for new and seasoned Heresy players alike to understand this essential event in the Horus Heresy and is a great source of inspiration for early Heresy themed forces. We now know that Shattered Legions are coming this year, and this event is where the main three Legions first became shattered and so is essential reading if you plan any kind of Iron Hands, Salamanders, or Raven Guard mixed forces.

New Legendary Mission
After the lore comes the new Legendary Mission, the First Wave, representing the first big offensive by the Loyalist forces against the Traitors. A Legendary Mission is a mission designed to replicate a specific historic battle in the Horus Heresy that is not necessarily meant to be balanced or put players on equal footing.
Using long table edges, the Attacker Loyalist forces must gain a foothold by controlling centrally deployed Objectives while the Defender Traitor player must kill them all, introducing the first true “Kill Points” objective in the game thus far outside the Vanguard (X) rule. The Loyalists use a staggered deployment map wherein any Vehicles must be deployed further back while all other units get to deploy further up. While meant to depict the Istvaan V Dropsite Massacre, this mission could be used with any forces.
It definitely seems that the Attackers have their work cut out for them, but such is the case with many of the Legendary Missions written for the Heresy; lopsided missions and armies can sometimes tell compelling stories on the table top! While this mission is not especially balanced on its face, it is up to the players to forge their own narrative and tell the story they want to tell. However, the big thing that this mission introduces to the Heresy player and Event Organizer toolbox is the Battlefield Assets mechanic.
Battlefield Assets
For those of you as long in the tooth in this hobby as I am, you may remember the old Cityfight and Cities of Death expansions that released back in third and fourth edition 40k respectively (introducing the Vostroyan Firstborn for the first time in glorious pewter) and then coming back briefly in eighth edition. This expansion introduced a distinct ruleset for playing games in the tight, claustrophobic confines of an industrial city with bespoke rules and missions to represent your forces fighting close, bloody firefights in alleys and through ruined buildings. One such mechanic was the Battlefield Assets in which a player got a certain number of points to spend on being able to shape the battlefield to their liking, be it leaving ammo reserves for their forces in strategic buildings or leaving nasty IED booby traps for their opponents to stumble into. While we have already been told that City Fight will return for Heresy in a future supplement, it is nice to see this mechanic return outside of that setting.

Credit – Games Workshop
Battlefield Assets is just a self-contained special rule that has been added onto the Legendary Mission, but can be easily tacked onto any custom mission and making it an easy framework for players to use. Each player gains a number of Asset Points based on the size of the game being played, usually 2 to 5 for 0-3,500 point games and may select from the list of assets based on what role they are playing in the game, Defender or Attacker. These are then placed on the table by the controlling player, each asset stating where it can be placed, and are represented by 40-60mm tokens (per SG’s size recommendation in the book.) These tokens have no effect on gameplay other than what they actually DO, allowing models to see and move through them freely and opening up a world of cool modeling possibilities. This also means your opponent can’t take your fun away by shooting them before they go off. Most of these assets are some variation of mine traps; melta, grav, and frag. There is also a “-1 to all Characteristics” Disruption Emitter trap for Attackers and a Contingency Device bomb that goes off if the controlling player Falls Back from a combat near it. Lastly there is the tried and true Ammunition Dump, increasing the FP of a small arms weapon the unit uses in a shooting attack, and the Strategic Cogitator Array which allows a player to add +1 to the “X” value of a Secondary Objective in that mission by a Command Unit “requesting new orders.”
Overall this is a fantastic mechanic and leaves a lot of room for expansion. I think this special rule is an EO’s dream and allows for a creative mission writer an easy way to insert some extra flavor or tactical level into a mission. I love the flavor of these and they don’t seem overpowered at all to the point people might not be afraid to take them in more games. I’m very excited to see what future expansions/City Fight holds for these assets!
New Astartes Units
Man, barely into the new edition and we’re already getting new units for Astartes! It’s good to be the Kings.
First up is a new Command unit, the Master of Descent. This new 115 point jump pack only consul is essentially a combination of a Master of Signals and a second edition Warmonger that automatically passes his and his unit’s Reserves roll as well as allowing any other unit to automatically pass their Reserves roll once he’s on the table so long as they deploy via Deep Strike. In addition, he and his unit (specifically Antigrav units only) can arrive via Deep Strike on the first turn, and he unlocks a new Auxiliary Detachment called Planetfall Speartip that has a Retinue and Two Prime Elites slots that must be filled by Praetorian Command Squad with Jump Packs and Veteran Assault Units respectively. No notes, I love this guy. Since you can only Deep Strike one unit a turn in third edition now, it definitely makes sense to bring him and his unit in first turn, then let each next Deep Strike unit automatically pass their Reserves rolls. If you plan to bring any unit in via Deep Strike, much less an Antigrav unit, he seems like a no-brainer. Bring him and his unit in Turn 1, then bring your Javelins, Scimitars, or Assault Squads down in subsequent turns to guarantee a Deep Strike into rear armor or onto an important Objective (though note you cannot Charge out of Deep Strike anymore.)

Next up is the Augur Command and Control Squad, a new support Retinue unit. This unit allows a single unit within 18”, following a successful IN check, to reduce the Reaction cost of a Reaction by 1 to a minimum of zero once a turn. Paired with a Praetor, one of these in your army can easily get you up to being able to make the standard three Reactions base a turn that we were used to from last edition, going up to four in games of 1,500 – 3,500 points. For Ultramarines, this can get you up to a whopping 4/5 Reactions a turn base depending on the size of your game and seem like an auto-include for that army at least. With 2W base (for a total of 8 Wounds for the unit), these guys are also surprisingly beefy meaning they will need to have some decent firepower directed at them to pick them up. The fact that these guys take up a Retinue slot means that some players may feel that the juice isn’t worth the squeeze on this unit. However, we think pairing these guys up with a Heavy Support Squad or some other long range support unit and castled up next to one of the new Arachnae gun platform handing out it’s 5++ makes a neat little self-contained Reaction combo. The designers recommend using the new Rapier crew models for this unit (coming with four models base) but to me this screams “make a cool ‘logisticae’ style command unit” conversion.

Lastly, we have the Hyperios Missile Tank, which hilariously is just a Scorpius with one of the new missile Tarantula turrets stuck on top of it. Nothing else much to say here; it’s an anti-air Scorpius, packing the 48” FP3 RS7 AP3 D2 Skyfire, Rapid Tracking profile that the tarantula comes with. This is more useful than it first seems, since Skyfire weapons no longer require Snap Shots against non-Air targets, so these guys can still perform Interceptor Reactions with the missile launcher even though it isn’t a Defensive Weapon and at the very least can chunk out 3+ Save 2W models like vets with relative ease. I would say these guys are by no means an auto-include, but they are definitely useful, fun, and a way to get more bang for your model buck. They are also a comparatively cheap (for dollars and points) way to get that anti-air into your army. And trust me, with Flyers being able to do what they do this edition and free Interceptor from augury scanners being gone, you are probably going to want some kind of source of anti-air in your army even if a nominal one like this.

I really really like the trend this is setting for Specialist Games letting you “double up” on your models, and I hope it continues. Takes a bit of sting out of the reduced options and load outs this edition brings.
New Prime Advantage
Last new thing this book gives the Legiones Astartes is the In interdiction Cadre Prime Advantage. This grants a Tactical or Despoiler unit filling the Prime slot the Expendable (1) and Concealed Positions special rules. Concealed Positions give the unit access to the Concealed Ambush Advanced Reaction. Just like the Iron Warriors in the Dropsite Cinematic, if you leave the Concealed Positions unit in Reserves, when an enemy unit ends a Move these guys can pop up 5-6” away from that unit and immediately make an out-of-sequence Snap Shot Shooting Attack or a Disordered Charge.

The free Snap Shots and possibility of a Disordered Charge (not getting a setup move, allowing Volley Attacks by the Target Unit, and being an eminently failable 5” Charge) is cool and all, but I think the utility of being able to pop a Line unit anywhere on the table at any time can create huge issues for your opponent. It creates the potential for HUGE plays, especially near the end of the game or when you can declare a Counter-Offensive if you are behind on points. At the very least, this unit is now a problem that has to be dealt with and cannot really be ignored but also gives few or no points for getting killed, especially considering the potential for clever positioning by a savvy player. Keeping 200 points of Troops off the table isn’t too much of an ask in my opinion, and at the very least will make your opponent think twice about repositioning a unit knowing you can pop these guys up at any time. An amazing tool for a strategically minded commander to have in the box.
Final Thoughts
All in all, Specialist Games has packed a lot of neat content into this fairly short book, being sub-100 pages. We don’t yet know the price point for this Journal, but if it is anything like the Old World Arcane Journals, the damage shouldn’t be too bad. That said everything in this book is worthwhile, and while it isn’t a lot, it is all thoughtful, flavorful, and efficient. If they keep this trend up with other key battles in the Heresy and other factions, I think we will have a great time this edition.
With us now knowing that GW will be dropping pretty much all the currently playable factions by the end of the year, we have the potential for a lot of cool expansions and content to look forward to. Thanks Specialist Games, keep up the good work!
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