The 10th Edition 40K Index Updates and Errata Review (July 26, 2023)

Today Games Workshop made good on some of its promises of the past few weeks by delivering a large set of Index updates and errata with an eye on fixing mistakes and issues in the game’s datasheets. There’s enough of these that GW published a pdf outlining all the changes (which you can find here), and while most of them are not significant enough to matter (we suspect most people were ignoring the Chaos Rhinos which didn’t have Firing Decks), some of them do make a rather large difference in the game. As we go through the changes, we’ll mostly be focusing on those bigger changes which have a major impact on the game and faction balance.

What’s Not Here

Just as important as the changes made here are what’s missing – notably, there are no rulings or commentary updates, which means that a number of hot-button issues such as being able to Overwatch multiple times per turn via Stratagems have just been left unaddressed – though Tacoma gave us some insight into how GW might rule on those they ever choose to actually address ambiguous issues in the rules. Still, it’s frustrating that a number of large issues are still unresolved and being left up to the players and TOs to rule on.

Additionally, these are decidedly not intended to be balance updates, so while there are some things which have a major impact on balance, these are just intended to correct errors on the datasheets. Though in some cases it seems like “Wraithguard were an error, actually” is the conclusion we should take away here.


Adepta Sororitas: There’s one significant change here, which is that Dominion Squad bolters became Rapid Fire 1 (instead of Rapid Fire 2). They keep the ASSAULT rule, but lose about half of their effectiveness. This one always seemed weird but it also hurts to lose.

Adeptus Custodes: Nothing really changes here. The Knight-Centura gets a close combat weapon profile for when she loses her greatsword in other loadouts and surprisingly she’s S4. 

Adeptus Mechanicus: The Archaeopter Transvector now explicitly forbids KATAPHRON models from embarking, which doesn’t actually change anything. Even before the eratta, Kataphron Breachers and Destroyers could never embark in Transvectors because they are neither Skitarii models nor Tech-Priest models, so this errata quite literally does nothing. The only other changes are some cleanup on the Onager Dunecrawler and Kastelan Robot datasheets, but no real functional changes.

Agents of the Imperium: Rogue Trader Entourages now lose the RETINUE keyword and so only count for your CHARACTER allotment.

Black Templars saw a few changes. Helbrecht is now a Chapter Master, The Castellan is a Lieutenant, Primaris Sword Brethren now have a Lightning Claws profile and can even be given a set for every five models in the unit. Also the unit size was fixed.

Blood Angels mostly see some typos fixed on their vehicles; the Baal Predator picks up Deadly Demise D3, while the Furioso and Librarian Dreadnoughts gain the SMOKE and DREADNOUGHT keywords. Also the Death Company Dreadnought gains the DREADNOUGHT keyword.

Dark Angels see some minor adjustments to fix typos. Nothing major.

Grey Knights land raiders now move 12” and the Brotherhood Chaplain is a LEADER. The benefit from Death from the Warp now lasts until the end of the turn instead of the end of the phase, making it actually have a use.

Astra Militarum

There are quite a few changes to the Astra Militarum, though only the change to Ursula Creed has a major effect on the army and how it plays. 

  • The Armoury card now has a special call-out for certain weapons to have BS3+ when equipped by a MILITARUM TEMPESTUS model and not just a Tempestor. Given this only applies to some pistols, it’s mostly whatever.
  • The Exterminator Autocannon in the Armoury section was updated to match the Leman Russ Executioner datasheet, so it has RAPID FIRE 4 instead of SUSTAINED HITS 1. So now Tank Commanders get the proper weapon for their turrets instead of having a weird nerfed version.
  • Death Korps units no longer lose a lasgun to take the vox-caster while Infantry Squad weapons team now count as two models for wargear options.
  • Ogryns gained a close combat weapon for when they give up their huge knives for a shield.
  • Taurox Prime frag missiles are now S4 and not S9, which was a hilarious and insane typo.
  • Ursula Creed’s Tactical Genius ability can now only be used to issue an order to REGIMENT units, helping close a very dangerous loophole with Imperial Agents.


There are quite a few changes here to the most complicated tiny faction in the game, but most of them are simply typos or cleaning things up, like removing the storm bolter ranged profile from the Fortis team, which cannot take storm bolters.

  • Kill Team Cassius gets some adjustments. The power sword on Gameon Zydrael (the Dark Angels dude) becomes 3A, S5, AP-2, while the Heavy Flamer actually gets a heavy flamer profile at S5 AP-1 (instead of S2 AP0). 
  • Proteus Kill Teams lose quite a bit of punch as their Terminator Thunder Hammers drop to 3 Attacks (from 4), though their Twin Boltgun now has 2 shots instead of 1. 
  • Spectrus Kill Teams got a nerf in that Special-Issue Bolt Pistols are now more sensibly 1 attack each, but they get a buff in that the team can change out its sniper rifles for carbines and las fusils now, and trade their combat knives for bolt carbines.

Imperial Knights

In a bit of much-needed clarification that actually got added, the Imperial Knights Code Chivalric was updated. First, the 3 CP you gain for completing your deed is now exempted form the rule switch limit the maximum number of CP you can gain per round to 1, and more importantly, Lay Low the Tyrant now specifically only lets you re-roll a single hit roll of 1 and a single wound roll of 1 when you shoot or fight. This puts to bed the rather insane argument you could re-roll all hit and wound rolls of 1 that rose from the ambiguity in the prior wording. This is one of those nerfs that isn’t really a nerf as most events were playing it as a single re-roll.

Additionally, the Squires’ Duty Stratagem now only affects attacks made against the targeted enemy unit, so your Armigers don’t just gain extra AP and damage against everything. Again, another weird loophole resulting from bad wording.

Space Marines

There are a ton of changes to Space Marines, mostly owing to the fact that they had a ton of datasheets to make errors on. The bulk of these changes are where they’ve gone through and changed the damage characteristic on grav-pistols and grav-guns to 2. This is a nice little upgrade that gives you much more reason to consider grav-pistols. Also Command squad Grav weapons are now 2 damage as well. Additionally, Librarians with Jump Packs can Deep Strike, Bike Captains can take Thunder Hammers, and Gravis Captains are back to 5” Movement, where they should have been all along.

Space Wolves

A surprising amount of changes for Space Wolves but again, most are just fixing typos like giving Leader to Cyberwolves, letting Canis Wolfborn have a bolt pistol, and removing the BS on the Stormfang’s auto-hitting weapon. The biggest change here is that Wolf Scouts have 2 wounds, fixing a major lore/fluff issue with the datasheet. That said, we’re not sure if they’ll stick around long enough for it to matter given the recent announcement about space marine scouts so who knows if this even matters.  


Most of the Chaos changes were fixing obvious errors, such as adding Firing Deck 2 to Rhinos. something we think most people were already playing with.

Chaos Daemons: Very little changes for our friends in the Warp. The Blue Horrors “Cackling Horrors” ability now works as intended, making enemy leadership tests harder instead of easier. While it was funny that their debuff actually helped enemies previously, it’s nice that RAW now matches the RAI. Meanwhile Burning Chariots gaining the FLY keyword and the Great Unclean One’s autohitting vomit attacks getting N/A Ballistic Skill are minor clarifications that many players probably didn’t even notice were wrong initially. 

Chaos Knights: Nothing has changed, for better or worse. 

Chaos Space Marines: Chaos Space Marines got a small but welcome set of quality of life changes. Rhinos getting Firing Deck 2 means units like Noise Marines and Havocs can do damage while staying safe inside. Predator Autocannons getting Rapid Fire 2 makes them more viable. Every other change was just basic wargear clarifications to units like Chosen, Raptors, and Traitor Guard.

Death Guard: Minor tweaks but nothing that changes their place in the meta. 

Death Guard Terminator Sorcerers’ Putrescent Vitality ability got clarified, as the clause about seeing an enemy unit that didn’t actually do anything got removed. Now it’s just good clean -1 Damage in the Fight Phase for the unit they’re leading on a 2+. 

  • Helbrute wording got clarified.
  • Daemon Princes getting Deep Strike opens up some fun Rapid Ingress plays. 
  • Minor clarifications to Cultist Ballistic Skill, and all of our Pistols are now Pistols.

Thousand Sons: Transports got slightly buffed, but nothing really changed. Rhinos gained Firing Deck. This is nice for Thousand Sons, as you can put 2 squads of Rubric Marines inside and have the Aspiring Sorcerers fire out. Land Raider Inferno Heavy Bolter and Defiler Lascannons got fixed to match similar profiles.

World Eaters: Very little changed. We got identical Rhino Firing Deck and Predator Autocannon tweaks as CSM, and now Favoured Of Khorne only gives you 1 Blessings re-roll per Battle Round, meaning you can’t double dip on the re-roll if you use the For The Blood God stratagem.


We’ll hit on Eldar and Genestealer Cults in their own sections. The rest are pretty straightforward.

Drukhari: Voidraven Bombers gain FLY (lol) and the splinter pistols on Wyches improved from ANTI-INFANTRY 4+ to 3+. 

Leagues of Votann: The Appraising Glare Enhancement was fixed and now actually does something, lasting until the start of your next Command phase so you can actually make use of the phantom extra Judgement Token on your target. Uthar was also fixed, and can now no longer give himself 6s for damage rolls he wasn’t able to make in the first place.

Orks: Ghaz can’t ride in Gorka/Morkanauts or Trukks anymore. Some twin big shootas got their range fixed (to 36”), Meganobz and Warbosses gained the MEGA ARMOUR keyword, and Mob Rule now lasts until the start of your next Command phase. On the whole, a negative. 

T’au Empire: A few changes here. Several units had their Accelerator burst cannons fixed, making them AP-1. In Stealth Suit teams the Shas’ui now has the unit’s homing beacon, and Sun Shark Bombers had their wargear reconfigured a bit in a way that broadly doesn’t matter. 

Tyranids: The only change here is to Barbgaunts, which now forces you to pick a single INFANTRY unit hit by their guns per Shooting phase to get the disruption debuff, making them much less of a split-firing nightmare.


One of the three big actual movers in this FAQ, Aeldari were hit with a few specific changes which have a major impact on the faction’s strength. 

  • Starting with the Autarchs, the Starswarm mode on the reaper launcher is now 1 damage, and the Autarch can take the fusion pistol without taking a banshee mask.
  • The biggest change here is probably to Wraithguard, who now no longer gain the PISTOL ability on their guns when using their War Construct ability. This now makes it much, much safer to just charge them, since fighting them now longer means getting shot off the table in retaliation. Additionally they got a second much-needed nerf to the Spiritseer, whose Tears of Isha ability now only happens in your Command phase, meaning you can’t get back two models per round. 
  • The Fusion Pistol on the Corsair Voidscarred is now D3 damage.
  • A bunch of units gained close combat weapons.
  • ANRATHE units can now be taken in Ynnari armies. 
  • Phantasm can no longer target AIRCRAFT.
  • The Twin Starcannon on the Wave Serpent now only has 2 Attacks (instead of 4). Additionally the Wave Serpent Shield ability can only be used in your Shooting phase, meaning it can no longer be used as a kind of pseudo-Overwatch.

These are some pretty big changes which certainly help to reign Eldar in a bit but still leave them as the obvious top choice. At the very least, they make Wraithguard less frustrating to deal with across the table.

Genstealer Cults

The other faction seeing large power level shifts are the GSC. The big change here is to Cult Ambush, which now duplicates the dead unit (so you get one-shot weapons back) and requires you to set up the unit wholly within 3” of the Cult Ambush marker you created. This is a significant nerf, since before you could easily chain models off the marker and on to other objectives or into aura range. Now you’ll have to be much more careful. The space may also be a problem, but that will mostly be with large bike squads which may not be able to wholly fit in that space. 

On that note, Atalan Jackals now only do their Demolition Run ability once per battle round. Anyone who has been hit with mortals 3 times in a round from this horse shit is currently rejoicing.

These changes blunt the faction a bit but don’t really curb their strength. We expect them to continue being the second strongest faction in the game. Many events were already letting you get back one-shot weapons on respawn, so that doesn’t change all that much. For those of you wondering why this matters, the GSC plan is to recycle Acolytes, put them back into reserves, then set them up inside 6” with Tunnel Crawlers and lob a new set of Demolition Charges. Again, this was something most events were allowing but now is much more codified thanks to the new wording.


On the less drastic, but still impactful side of things for Xenos we have the Necrons. The big change here is that Cryptohtralls no longer gift their units the ability to fight on death – that now only happens for the thralls. On top of that we had some changes to some of the bigger units in the army. FIrst, the Silent King’s Menhirs no longer explode – RIP to a hilarious mechanic. And the Obelisk now gives its movement debuff until end of turn, making the advance and charge modifiers actually matter. 

Finally the Transcendent C’Tan gained Reanimation Protocols, making them even tougher. Expect Sempiternal Weave Transcendents to start showing up a lot more in their new, completely unkillable forms. 


Final Thoughts

This is a good set of changes on the whole, fixing some clear issues that needed addressing. We’re still baffled by what wasn’t addressed, and would like to see some additional commentary in the next week, but for the time being, this is a good start.

Rob: At the very least, I personally am excited to see the Wraith guard change. What a miserable unit to play against.

Have any questions or comments? Drop us a note in the comments below or email us at