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Genestealer Cult Codex Review – 9th Edition Warhammer 40k

Games Workshop has blessed us with a brand new codex for 9th edition, and I won’t beat around the bush here; this codex is awesome. It has everything that a GSC player would want, with so many different army lists being viable. Whether you want to run a horde of aberrations as Twisted Helix, or create your own kind of playstyle with a custom cult, you’re sure to be satisfied with all the content in this book!

Detachment Rules

We’ll start off with the restrictions that must be adhered to when unlocking all the potential this book provides. All units must be drawn from the same <CULT> in the same detachment, and if you take a Patriarch, he must be the Warlord. If you don’t have a Patriarch, but do have a Primus or Magus, one of them must be the Warlord instead. You cannot give a Warlord trait to a character that isn’t in the HQ slot of the army. If you follow these rules, your Genestealer Cult detachments will unlock Cult Creeds, Stratagems and all the other usual stuff having a battle forged detachment unlocks. In addition, if your entire army follows these restrictions, you unlock Crossfire, which we’ll talk about later.

So we’ll start off with the brand new army-wide rules that GSC can fully utilise. First up is Conceal, which everything in the book has access to. With this ability, when you deploy a unit, you can choose for it to either be set up in ambush, or, if the unit is a Biker or Infantry unit, it can be set up underground.

If a unit is set up in ambush, it is instead set up as a blip in your deployment zone, and these rules are mostly the same as they were from 8th edition, with the exception that you can no longer deploy the first model from your unit outside of your deployment zone. These blips are revealed immediately if you have the first turn, or at the end of your opponent’s movement phase if you go second. If however, a unit is set up underground, then from the 2nd battle round onwards, you can deploy the unit anywhere on the battlefield following either of two restrictions:

  • You can either arrive anywhere outside of 8” from an enemy unit.

  • You can arrive anywhere outside of 6” from an enemy unit, but you cannot charge in the same turn.

This change is massive, and will be incredibly useful in our games. Giving an effective +1 to charge from reserves is so strong for our army, and the ability to set up Crossfire more easily by arriving outside of 6” is also great.


The next rule we’ll talk about is Summon the Cult. A unit can summon the cult in their command phase as long as the unit has been upgraded with a Cult Icon, or if it has the <CORE> keyword and is within 6” of an Acolyte Iconward. If both of these apply, you can do it twice, but note you can never exceed the maximum number of regained models as you would from just doing the ability once. For example, if you regain D3 models from Summon the Cult, then no matter how many times you use the ability, you can only ever regain 3 models per turn.

Neophytes regain D6 models when they summon the cult, and every other unit regains D3 provided it has access to this ability. I can see this being incredibly useful on bigger blobs of infantry, helping to swing Primary points before the end of the command phase comes around. The Cult Icons are quite expensive though, being 20 points per unit, but most lists will be running an Acolyte Iconward, so this extra rule is always welcome.


Finally, we have Crossfire. This is an awesome new ability that gives a significant boost to our shooting potential, as well as having some interaction with some abilities and stratagems that we’ll talk about later. If you shoot an enemy unit, and you hit with at least 5 attacks that are damage 1, or 1 attack that is more than damage 1, that enemy unit gains a Crossfire token after all of that unit’s attacks have been made. Any further attacks that target a unit with a Crossfire token gain +1 to hit. Before we even get into further benefits from this, this is already a huge benefit to our army, and makes a shooting unit actually viable now. Neophytes are back on the menu boys!

But that’s not all. When you shoot at a unit with a Crossfire token, if you can draw a line from your own unit to another friendly unit, and that line passes over the enemy unit with the Crossfire token, the enemy unit is considered Exposed. You also gain +1 to wound on your shooting attacks, and if you are also within 12” of the enemy unit, your attacks ignore cover. WOW. This really turns the shooting phase of this army up to 11, and with there being multiple ways to give Crossfire tokens to enemy units automatically, this is a powerful rule that will come up in every single game. Awesome!


Warlord Traits

So a bunch of these traits are mostly the same as before with some slight tweaks. Alien Majesty still adds 3” to your aura abilities, but also increases the range of your targeted abilities by 3”. Shadow Stalker still gives your warlord a flat -1 to hit, but the one I’m most tempted to take on my Patriarch is Prowling Agitant. When he is selected as the target of a charge, once per turn, he can make a move of 6”. This will really help his survivability, as most armies rely on shooting the stuff around characters and then charging them to finish them off. Preternatural Speed is also interesting, allowing your Warlord to reroll hit rolls and always fight first.

Overall the warlord traits are all decent, but none stand out as an auto take, with each having a viable role in an army.

Psychic Powers

Pretty much all of these have seen some kind of change, with Mind Control being totally changed in its entirety. It is now WC6, 18” range and gives a -1 to hit de-buff on an enemy unit. If the casting roll was equal to or higher than the enemy unit’s leadership, they also suffer from -1 to leadership and combat attrition. 

I think the three powers that you will see most often will be Mass Hypnosis, Psychic Stimulus and Might from Beyond. Mass Hypnosis is still WC7 and 18” range, but it now forces an enemy unit to fight last and suffer -1 to their attacks characteristic. Psychic Stimulus is WC6 and 18” range, and still allows a friendly unit to advance and charge, however it has some additional benefits now too. It also allows you to fall back and shoot and charge, as well as ignore the penalty to your hit rolls for advancing and firing assault weapons. And last but certainly not least is Might from Beyond. It’s exactly the same as before, but it is now WC6 and only gives +1 attack. So it’s easier to cast, but has less of a buff. +1 attack on an entire unit however is still very helpful, and this will most often be cast on Acolytes or Aberrants.


There’s a whole bunch of relics in this new book, so I’ll talk about the ones that I believe are the biggest standout. First of all is the Unwilling Orb, which can only be given to a Psyker. This relic allows you to deny an additional power each psychic phase, and lets you deny powers from anywhere on the board, no matter how far away the caster is! It also gives you +1 to cast when you attempt to cast a Malediction or Witchfire psychic power. 

Another great pic in my opinion are the Wyrmtooth Rounds, which must be given to a Kelermorph. This allows him to exchange his shots per gun, or which he has 3, to instead shoot a single shot at 18” range, S6 AP-3 D3 (so a maximum of 3 shots). You can still generate additional shots by landing hits with this profile (as he retained that rule) however he loses the ability to snipe characters. This is an awesome relic that turns the Kelermorph into a great elite infantry killer with some utility. The Kelermorph innately has an ability that allows him to move after he has shot, so he can appear, shoot and kill some Custodes / Gravis marines, and then jump back into cover hidden from the enemy guns.

Finally, another awesome relic is the Amulet of the Voidwyrm. This nifty relic gives the bearer a 4++, as well as ignoring overwatch and set to defend whenever he charges. This is all the same from the 8th edition book, but it gained a brand new ability too; once per game, when an attack is allocated to the bearer, you can automatically treat the dice roll as a 6. A cool little boost in survivability that can definitely mean the difference between life and death for one of your characters.


OK, so there is a load of cool new stratagems in this book, so I’ll quickly fire through some of the standouts. Clandestine Goals lets you keep one of your secondaries hidden until you score points for it for 1cp. Bore Through lets your Industrial Weapons reroll wound rolls vs Monsters or Vehicles in the fight phase (and with Crusher Stampede being a thing, this is a great stratagem to keep around). Leaders of the Cult lets you generate two additional warlord traits for two of your HQ characters, provided that your warlord is a Patriarch, for 1cp. Monstrous Vigor gives a unit of Aberrants (or an Abominant) transhuman (wound rolls of 1-3 that target this unit automatically fail) for 1cp if the unit is <5, or 2cp if the unit is >5.

Now into some more complicated ones. Lurk in the Shadows got an amazing new ability that really adds some safety to your units. For 1cp, at the end of your movement phase, you can pick a Biker or Infantry unit on the board and place it back into reserves, OR, you can use it in the Fight phase after your unit has made its attacks, provided there are no enemy units within 6”. This gives some great survivability to an otherwise squishy melee unit that can charge in, kill a unit, then dive back into reserves. Note however, that it specifies when they arrive again next turn they must be further than 9” from the enemy, instead of Conceal which would normally allow you to arrive further than 8”.


Raking Fire, for 1cp, allows a unit of Ridgerunners to reroll hit rolls if the target unit is Exposed, as detailed in the Crossfire rule. Note however, that this only works if the enemy unit is Exposed as described in the Crossfire rules, and not through any other means (as there are some abilities and stratagems that cause enemy units to become Exposed even if there are no friendly units surrounding them).

An example of this is Pack Hunters. For 2cp, in the Shooting phase, pick an enemy unit within 6” of a unit of Atalan Jackals. Until the end of that phase, all <CULT> units that target that unit treat the enemy unit as being Exposed. And there are so many ways to trigger similar effects with different characters, it really opens up Crossfire into being a legitimately great army-wide rule.

Cult Creeds

All of the cult creeds have their own uses, each incentivising different ways to run your lists, as they should be. A few examples I’ll give are Twisted Helix, Four Armed Emperor and Hivecult. And finally, Cult Creeds apply to EVERY unit in your army, including vehicles!

Twisted Helix gives your units +1 movement, +1 strength, and wound rolls of 1-2 always fail when targeting these units. A little bit of extra survivability and an increase in strength is always great, allowing a whole bunch of your units to hit that important strength 5. The relic is also incredibly awesome; your warlord gains a Genomic Enhancement (the buffs that the Biophagus gives), and if you have a Biophagus in your army, you can instead pick two for him. Their stratagem, Monstrous Bio-Horrors, also helps with Aberrants clearing hordes, changing your damage characteristic to 1 but granting you an extra attack all for 1cp, and every enemy model you kill counts as 2 for the purposes of morale.

Four Armed Emperor is the “jack of all trades” cult of choice, giving your entire army reroll charges and the benefits of Light Cover if you are more than 12” away from the enemy. Their infamous stratagem, A Plan Generations in the Making, has been changed to match the new Agents of Vect stratagem in the Drukhari book. For 0cp, once per game, use when the enemy uses a stratagem. For the remainder of the game, when the enemy uses that stratagem, it costs 1cp more. Their Psychic power is also brutal; Undermine is cast on a 7 and has an 18” range, and forces an enemy unit to have -3 to their move, halve their advance rolls, and -2 to charge rolls. If you were terrified of a Dimachaeron or a unit of Genestealers ruining your day, this can put an immediate stop to that.

Finally, Hivecult is in my opinion the most improved of the famous cults. You still keep the fall back and shoot ability (still suffering -1 to hit when you do so) but gain some additional benefits. Units in your army can fall back / advance and still perform actions, AND units in your army can shoot without actions failing. A huge boost in power for the Hivecult, and of the famous cults, I think this one will be the go-to for a lot of competitive players. Fire Discipline for 1cp also gives a Crossfire token to an enemy unit before you shoot it instead of after, effectively granting you +1 to hit for 1cp. And their warlord trait really kicks ass too. Hivelord gives your warlord a 6” bubble of exploding 6s for <CORE> shooting attacks. Great with massive blobs of Neophytes and Jackals, but unfortunately that’s about it.


Now we move onto the custom Cult Creeds, and in my opinion, this is where the true power lies. You are given 4 “points” to play with, and each trait costs between 1-4 points, allowing you to mix and match to your heart’s content. War Convoy costs a measly 1 point, and gives all Bikers and Vehicle units in your army a 6+ save against wounds or mortal wounds. Agile Guerrillas allows your units to count as stationary in the shooting phase even if they advance or moved for 2 points. Martial, for 2 points, allows it so when a unit with the Crossfire keyword shoots at an enemy unit, provided you did not move in your turn, the unit counts as having a Crossfire token. However, it specifically states that you can not combine Agile Guerrillas and Martial together into a cult creed.

I think the true power lies in taking Impassioned for 3 points, and Industrial Affinity for 1 point. Impassioned is similar to the Space Wolves chapter tactic, giving your units +1 to hit in melee when you charge, were charged or performed a Heroic Intervention. Industrial Affinity means that whenever you attack with an Industrial Weapon, in both shooting and combat, you can ignore any and all hit roll, ballistic skill or weapon skill modifiers. This means, your entire army in melee will effectively hit on 2s with Industrial Weapons at all times, regardless of any modifiers that your enemy might throw at you. It also means with Crossfire, you can expect your shooting Industrial Weapons to always hit on 3s. An awesome combo that I think you will see a lot of on the table, and I will certainly be using it myself.


Alright, onto the juicy stuff! A huge amount of these units got changes to their weapons, abilities, statlines etc, so I’ll be going through the biggest changes. First up, we have Aberrants, that I know a lot of people are keen to know if they’re good or not. As previewed on Warhammer Community, all Aberrants are now equipped with Heavy Industrial Weapons, which are S+3 AP-2 D3 for some serious heavy hitting. They also gained a point of toughness and an extra wound, making them S5 T5 and 3W each. They kept their -1 damage ability, however they did lose their 5+ shrug. But with a Biophagus, he can give a unit of Aberrants a 5+ shrug for the game! Considering these guys now cost 30 points each, I definitely think they’re worth including in a lot of lists, as they fill a role that we haven’t had since the army was introduced, a genuinely tanky unit that can sit on an objective and guard it.

Purestrains also got a massive buff in both their abilities and their statlines. They are now 4 attacks base, and their rending claws are now always AP-3. They also got a boost in durability, with their Invulnerable save improving from a 5+ to a 4+. Despite now only being able to take these guys in 10 man units maximum now, they are just straight up fire. Put 10 of these guys underground and your opponent will be constantly afraid of exactly what they can do!


And now, for the biggest improvement in the codex, we have the Goliath Rockgrinder. This thing is just great now. A combination of buffs to their shooting (Seismic Cannons got an increase to their AP and strength), their melee (they are now WS 3+ with the Drilldozer blades) and their durability (a 3+ save and flat -1 damage), for 110 points, these things are great. I expect to see a lot more of these guys, and I’m happy to finally have a reason to paint up the three that I have!

Proficient Planning

Now we come to my absolute favourite part of this book. These are upgrades that any unit can take, although some are restricted and state which units are able to take them. These range from costing 10-20 points, and you can take as many of them as you like, but you cannot take any of them more than once. Most of these are designed to help with your units arriving from concealment, as well as increasing your ability to control the board and help apply Crossfire tokens. 

The one that I imagine most people will be drawn to is A Trap Sprung. Costing 15 points, this allows a unit with the upgrade to charge 3d6, discarding one dice, the first turn they are set up from conceal. Combined with the innate ability to arrive >8” away from the enemy via conceal, this ensures that whatever you want to make the charge, will most likely make it. A very important upgrade that will see use in almost every list.


From Every Angle costs 10 points, and allows you to place the unit in Strategic Reserves for no CP investment. And when they arrive from reserves, they count the battle round as being 1 turn higher than it is. It even specifies that this allows the unit to arrive turn 1. At first glance, this sounds absolutely amazing, but I’m not quite convinced it’s all that great. You arrive via strategic reserves, so you must arrive >9” from the enemy and will most likely have no other benefits to increase the chance of making the charge. It can be decent on a shooting unit I suppose, but I will have to playtest to find a unit that it is worth using on.

And finally, my favourite of the upgrades is Excavate. As long as the unit with the upgrade starts the battle underground, at the resolve pre battle abilities step, you can pick a terrain feature anywhere on the battlefield. That terrain feature loses the Light Cover, Heavy Cover, Defensible and Inspiring traits if it had them, and gains the Difficult Ground trait. This is the most expensive of the upgrades at 20 points, and whilst I can see this not always being useful, it is just so damn cool.

Potential List

Having a look at the new point values provided in the new codex and all of the new rules, I already have a list that I’m keen to try out as soon as possible.

Genestealer Cult Battalion - Custom Creeds (Impassioned + Industrial Affinity)

HQ1: Patriarch, Psychic Familiar, The Unwilling Orb, Mass Hypnosis, Might from Beyond, WARLORD - Prowling Agitant [150]

HQ2: Primus, Exacting Planner [95]

TR1: 20 Neophyte Hybrids, 16 Shotguns, 4 Seismic Cannons, Cult Icon, Perfect Ambush [215]

TR2: 10 Acolytes, 4 Heavy Rock Cutters, Our Time is Nigh [140]

TR3: 5 Acolytes [45]

TR4: 5 Acolytes [45]

EL1: 10 Purestrains, A Trap Sprung [155]

EL2: 5 Aberrants [150]

EL3: 5 Aberrants [150]

EL4: Kelermorph, Wyrmtooth Rounds [80]

EL5: Biophagus, Alchemical Familiar, Alchemist Supreme [65]

EL6: Nexos, Cranial Relay [50]

FA1: 3 Achilles Ridgerunners, 3 Missile Launchers, Flare Launchers [240]

HS1: Goliath Rockgrinder, Heavy Seismic Cannon [110]

HS2: Goliath Rockgrinder, Heavy Seismic Cannon [110]

HS3: Goliath Rockgrinder, Heavy Seismic Cannon [110]

DT1: Goliath Truck [90]

Total points - 2000

Starting CP - 10

The list is designed to be hard hitting in both the shooting and fight phases, making use of crossfire tokens given out by the Nexos, and the Neophytes jumping in to demolish something with their Seismic Cannons. The Kelermorph is a great utility character, picking off either large bunches of infantry or even weakening some smaller vehicles with his incredibly powerful Wyrmtooth Rounds. 

The two minimum sized Acolyte units can guarantee some points on the upcoming Retrieve Nachmund Data, and being GSC the list can always do well on Engage on all Fronts. My last pick will often depend on what the other player has brought, but the Ambush secondary is always a decent pick to fall back on. It will never max 15, but most games you should score around 8 points on it.

Final Thoughts

Overall, I think this is my favourite book that Games Workshop has published since 9th edition began. Not only is the codex itself powerful and versatile, but it also stays true to the core of the army and how it should play. It’s really thematic and rewards you for strategic play. Plus, it’s always nice seeing the Xenos armies getting great books!

The new way to build your own custom creed is just great, and I really hope the upcoming codexes in the future follow the same kind of system. Proficient Planning really does just take this army to a new level of flavourful, and I’m more than excited to be able to use these new rules on the tabletop.

Thank you so much for reading, and keep an eye out for when we post our first written battle report with the brand new Genestealer Cult rules hopefully in the near future!