The Warhammer 40k March 2025 Balance Update: Imperium Factions

It’s Balance Dataslate time once more, bringing joy/terror to 40K players worldwide, and sowing the seeds of a whole new metagame. As always, we’re unpacking the changes and the impact across the game’s factions, and in this article we’ll be covering the Imperium factions, specifically the non-Space Marine varieties. That means the Adepta Sororitas, Adeptus Custodes, Adeptus Mechanicus, Astra Militarum, Imperial Agents, and Imperial Knights.

The rest of our regular Dataslate coverage can be found at the links below:

This time around there are also four new Detachments and an Index update, giving three factions that have had their Codexes for a while some new toys, and unleashing a whole raft of changes and a new Be’lakor-themed detachment for Daemons. These can be found below.

Thanks to Games Workshop for providing us with a preview copy of the Balance Dataslate and associated content.

Adepta Sororitas

Points Changes

  • Discounts:
    • Arco-flagellants -10pts for 10 (no change for 3)
    • Celestian Sacresants -5/20pts
    • Dominion Squad -10pts
    • Repentia Squad – 5/10pts
    • Seraphim Squad – 5/20pts
    • Zephyrim Squad – 5/10pts
  • Increases: None

Rules Changes

Miracle Dice are once again generated for each Sisters unit that is destroyed rather than one per phase.

Impact

Penance Paid? Winner

Thoughts

TwoHorse: The previous dataslate nearly disappeared the faction. Play-rate plummeted, those few brave souls who took the ladies out for a spin generally performed poorly at events, and photo-evidence of apostasy crept into Sisters hobby channels everywhere. Fortunately this partial reversal of the previous slate’s Miracle Dice changes should breathe interest and viability back into the faction as a whole, and the points changes should enable new melee-focused builds not seen since the Codex was released. We’re enthused to see the overcorrection from the December slate has been walked back a bit with new options on top.

The focus on cuts to little-used datasheets rather than the previously-ubiquitous shooting options is also a welcome boost for internal list diversity. Zephyrim and Repentia have been nigh-unplayable since the Codex dropped, and Sacresants have been rare outside of one-off appearances in Hallowed Martyr lists to tote around the Suffering/Strength Palatine, so it’s exciting that these awesome models might finally see the table.

The cuts to Sacresants in particular and the Miracle Dice change push Champions of Faith into viability (although not being able to Bless units in transports like the other similar Grotmas detachments still hurts). The cuts to Repentia probably don’t do enough to get Penitent Host over the edge when Hallowed Martyrs is right there to make better use of the Sacresant and Arco cuts, but we’d love to be wrong and it’s great that we can even consider it. Likewise Army of Faith starts to look playable with the addition of additional units and additional Miracle Dice. Bringers of Flame remains heavily constrained by the changes to its detachment rule, but the infantry cuts here should let players squeeze another activation or two into their lists, so expect to see this detachment back in action as well.

Overall these changes are a welcome step in bringing Sisters back into the game, and those handful of die-hards that have kept the faith for the last few months will find their patience rewarded with more units and a functioning army rule.

Adeptus Custodes

Points Changes

  • Discounts:
    • Aleya -10pts
    • Custodian Guard -10pts per squad (not per model).
    • Knight-Centura -15pts
    • Shield-Captain -10pts
    • Allarus Shield Captain -10pts
    • Bike Shield Captain -10pts
  • Increases:
    • Blade Champion +10pts
    • Custodian Wardens +10pts per squad
    • Venerable Contemptor Dreadnought +10pts
    • Telemon Dreadnought +10pts
    • Augury Uplink +10pts

Rules Changes

  • New Detachment! See here.
  • The Unstoppable Stratagem in Solar Spearhead can now be used in your Charge phase as well as your Movement phase.

Impact

Slight Loser

Thoughts

Wings: It’s pretty clear from recent builds that the internal balance of Custodes units hasn’t been quite right, as more and more builds essentially only use Warden/Blade Champion units as their Infantry core, with regular Custodians left on the shelf. These changes look like an attempt to slightly rebalance that, incentivising Custodian Guard and regular Shield Captains, plus also taking the all-in Dreadnought spam builds in Solar Spearhead down a notch. Like a lot of cases where this kind of rebalance is attempted, the new opportunities don’t outweigh the benefits, so the faction takes a little bit of a hit, but cheaper Custodian Guard genuinely is nice, and the Bike Captain dropping alongside the regular ones is beneficial, as plenty of builds are running one now.

Custodes also get a new detachment aimed at encouraging heroic charges, which gives you quite a lot of incentives to take a couple of bike captains, so if you pine for the days of many, many jetbikes, go take a look at our thoughts on that.

TheChirurgeon: The update to Unstoppable is pretty nifty, since you can now use it to charge through walls and the timing change – making it any time in the Movement phase instead of the start of the Movement phase – means that if you’re advancing you can wait until you roll to apply the Stratagem. If you’ve ever been caught out on the timing for this one, you can breathe a bit easier.

Adeptus Mechanicus

Points Changes

  • Belisarius Cawl -15pts
  • Tech-Priest Dominus -5pts

Rules Changes

None

Impact

Very Slight Winner

Thoughts

Wings: No major changes to AdMech, with the gamble seeming to be that taking the top metagame players down a few notches will allow them to flourish. This is probably a little optimistic – there certainly are some builds that are nearly there, but they feel like they’re far enough behind that a little more of a lift would have been welcome. It is, to be fair, pretty hard to work out where you give boosts, as most of the units are extremely cheap already, but maybe some cuts to things like small units of Breachers/Robots or some of the Enhancements would have worked? Cawl probably does start showing up in quite a few builds at his new price, so that’s something.

Agents of the Imperium

Points Changes

  • Culexus Assassin -15pts

Rules Changes

None

Impact

Very Slight Winner

Thoughts

Wings: Look, if you go purely on GT win rates this is actually justifiable, because the very small number of players determined to win a tournament with the Agents have gotten very good at going 4-1 or 3-2 at most of their events. They actually had the highest win rate in the game on the 1st/2nd March weekend, just with a sample size of, uh, four players.

In the real world – no great changes here, this is still 40K on hard mode, horde Fleet or (if you’re brave) Execution Force are your best options. The cheaper Culexus Assassin is mostly relevant as it drops the floor price of a quality Lone Operative for other Imperium builds, so might see use on that basis.

Astra Militarum

Points Changes

  • Cadian Heavy Weapon Squads +15pts
  • Catachan Heavy Weapon Squads +15pts
  • Field Ordnance Battery +10pts
  • Tempestus Command Squad +10pts
  • Tempestus Scions +5pts per 5 models
  • Bombast-class Vox-array +10pts

Rules Changes

  • Bridgehead Strike’s Fire Zone Purge now gives Scions +1 to Hit instead of Wound in a turn they arrived or disembarked.
  • Bridgehead Strike’s Firing Hot stratagem goes to 2CP, and only works against targets within 12”.
  • Krieg Combat Engineers take a major hit on their Remote Mine, which:
    • Drops to 9” range.
    • Requires the target to be visible.
    • Now does d3 Mortal Wounds to normal targets, and 2d3 to VEHICLE/FORTIFICATION targets.

Impact

Loser

Thoughts

Wings: No huge surprises here – Bridgehead Strike has been wildly overperforming compared to anything else Guard can do, to the point that it’s pretty hard to assess the quality of the rest of the Codex. This (fairly brutal) set of updates means that Bridgehead will have less stuff on the table, and massively reduces its ability to deal with hull-heavy foes. I don’t think this kills the list entirely, but it increases the counters available significantly, and probably encourages the adoption of variants running Dorn Commanders for some heavy lifting – which in turn makes it less of a skew in terms of dodging enemy anti-tank.

Outside of Bridgehead, the latest round of “what if we made mortars really cheap?” is once again immediately cancelled, and Krieg Combat Engineers turned out to be way too good as threat projection out of Transports with the number of Mortals they could drop between a mine and free Grenade. Their price tag is maybe a little harsh now, but they’re still pretty good in their role, so we’ll see how that plays out going forward. 

All together, this clearly hurts Guard, and feels like an exercise in improving data collection across the whole codex so they can get a proper tuning pass in the next dataslate.

TheChirurgeon: Combat Engineers not needing line of sight was the kind of bullshit the game just doesn’t need and I’m glad it’s gone. As for the rest of the faction, it’ll be interesting to see what happens. I’ve seen some top players suggest that Hammer of the Emperor is the best way to run guard, and Recon Element looks like it has promise. Mortars going up is kind of funny, because I have yet to feel like they actually pull their weight, even against T3 targets. I feel like they’re a trap, even: Whenever I come up against a guard opponent running nine mortars, they always throw them at the single unit of ten Cultists I have on my home objective, and somehow only ever manage to kill five of them, leaving me free to sticky the objective and get on with my life. The output just isn’t there.

Grey Knights

Points Changes

  • Interceptor Squad -5pts per 5 models

Rules Changes

  • Warpbane Task Force’s re-rolls no longer work when firing Indirect.

Impact

Neutral to Very Slight Winner

Thoughts

Wings: Very limited changes in Grey Knights other than them being another casualty of a “whoops we made indirect too efficient again” correction. RIP to spamming three Purgation squads. Despite that, the faction as a whole may win out of this by dint of standing still. Slightly cheaper Interceptors is fairly immaterial, but Grey Knights have some strong builds that couldn’t quite consistently tangle with the top tier stuff, so a major hit to those could set them up for success, though eye-watering rokkit volleys could put paid to any Terminator dreams.

Imperial Knights

Points Changes

  • Knight Castellan -30pts
  • Knight Valiant -30pts

Rules Changes

None

Impact

Winner

Thoughts

Whether or not the actual changes have much impact here, Imperial Knights do very well by coming through this dataslate with the current Armiger price tag intact. They’re already operating as a top army, so watching Bridgehead and Marines take major hits without anything similar landing on them is exceptional. People are definitely going to try Valiants out of Stratagic Reserves too, so we’ll see how that plays out.

Final Thoughts

The Astra Militarum needed the biggest hits here and they got it, with Bridgehead dropping substantially. Sisters needed a lot of help and received it as well, and Admech and Knights mostly stood still, standing to gain as a result.

That’s it for the Imperium factions, but there’s plenty more to unpack across the game, so make sure you check out the rest of our coverage, which you can find linked from the top of the page or from the Overview.

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