Ruleshammer 40k: T’au Empire

Welcome Ruleshammer readers and T’au enthusiasts to Ruleshammer 40k: Tau! This article will server as a hub for all rules issues that need addressing for the Greater Good. Read on for Tau rules, click the banner below to read the Ruleshammer Compendium! Last Updated: 2022-03-24

Current Q&A

Leadership use Auras and Modifiers

If an unit has a modifier to their leadership (such as -2 ld for being in range of Night Lords aura) but also has a friendly unit nearby that lets you use their leadership (such as a chaplain/inquisitor) who isn’t in range of the debuff, do you roll leadership using the chaplains current leadership (unmodified) or just copy their LD value then apply the modifier? – Dave

This is a question that has been debated frequently at Goonhammer HQ… and it’s one that I still don’t think we’ve ever actually agreed on an answer to before getting exhausted of debating it. To my read, the issue really boils down to “is using the Ld of another model replacing the Ld characteristic of the model attempting to use another’s Ld?” If it is replacement, then the Modify Characteristics rules cover that and it’s before modifiers:

Modifying Characteristics

If a rule instructs you to replace one characteristic with a specified value, change the relevant characteristic to the new value before applying any modifiers that apply from other rules (if any) to the new value. Regardless of the source, the Strength, Toughness, Attacks and Leadership characteristics of a model can never be modified below 1.

But I’m not sure “using the Ld of another unit” is instructing you to replace one Characteristic with another. The ability worded isn’t clear on if it is or not.

Spiritual Leaders (Aura): While a friendly DEATHWATCH CORE unit is within 6″ of this model, models in that unit can use this model’s Leadership characteristic instead of their own.

There are also instances where these abilities confer no actual benefit if they were subject to the same modifiers; if the Chaplain is near a unit of Space Marine Terminators for instance, both have a base Ld of 9.

Unfortunately without an FAQ there’s really not a RAW answer to this in my opinion. I have a preference, but I’d be hesitant to say it’s got much support in the rules outside of there being a void. My preference is to play that if the sharing Ld provider (the Chaplain) is not affected by the modifier, then units using their Ld can use it unmodified.

Some questions below either have pretty odd and often arguably unintended RAW interactions with other rules; if a question probably needs an FAQ to clarify things then I’ve included a “Pre-FAQ Suggested Play:” to summarise how I would suggest the issue be resolved.

Also I suggest reading my guide to the Battlesuit/Big Guns Never Tire rules!

Are Tau Markerlight targets declared like weapons?

No. Let me elaborate on what I mean here: When Markerlights were weapons their targets were declared as such. If a unit of Pathfinders had 10 Markerlights you needed to declare their 10 targets before resolving any attacks with the “weapon,” despite these attacks doing no damage. This rule applied:

When a unit shoots, you must select the target unit(s) for all of the ranged weapons its models are making attacks with before any attacks are resolved.

However in the 9th edition Codex: T’au Empire, Markerlights are specifically not weapons, they are wargear and they are no longer “shoot” they just determine which models in a unit can resolve the Markerlight action fully:

Fire Markerlights (Action): One or more MARKERLIGHT units from your army can start to perform this action at the start of your Movement phase. AIRCRAFT MARKERLIGHT units can perform this action. The action is completed at the start of your next Shooting phase. If this action is successfully completed, for each model in that unit that is equipped with one or more markerlights, for each markerlight that model is equipped with, select one enemy unit within 36″ of that model that would be an eligible target for that model if its unit had been selected to shoot, and roll one D6: on a 3+, that enemy unit gains one Markerlight token.

The only weapon-like element of them left is that the target for each one needs to be a unit that would be eligible if you were selecting a shooting target. They’re still not weapons though so you don’t need to declare where all 10 Markerlights from a Pathfinder unit are going before resolving any of them. You can slow roll them one by one into a particular target and then once you reach how many Markerlights you want to have on that unit, you can carry on with any remaining attempts into other targets.

Mont’ka and Zephyr’s Grace

Had a few people ask about how these two interact; and if Mont’ka’s remain stationary effect has an impact. My interpretation is that it doesn’t affect this ability from working.

If this invocation is inspiring, select one friendly T’AU EMPIRE CORE unit (excluding FARSIGHT ENCLAVES units) within 6″ of this ETHEREAL. Each time a ranged attack is made against that unit, if it did not Remain Stationary in your previous Movement phase, subtract 1 from that attack’s hit roll.

Because the stationary effect of Mont’ka only lasted until the end of the shooting phase, in the following turn the ability will no longer cause any Tau units to count as stationary. They will count as having made the type of move that they made in the previous movement phase.

However; interestingly there is a time when they might count as stationary and not trigger this and that’s if they are shot at by any “shoot on death” abilities during their own turn such as the Banner Ancient ability. For those attacks they would count as stationary still and not get the -1.

Firesight Marksman and Sniper Drones. Credit: Rockfish
Firesight Marksman and Sniper Drones. Credit: Rockfish

Markerlights on Vehicles and Drones – can they Advance?

I think the answer to this is currently “yes,” as there’s no specification of the type of move, and I think it might even be intended.

While a VEHICLE or DRONE unit is performing the Fire Markerlights action, that unit can move without that action failing. If it does, until the end of the turn, models in that unit without the VEHICLE or DRONE keyword that are equipped with any Markerlights are treated as not being equipped with any markerlights for the purposes of the Fire Markerlights action.

The reason i think this might be intentional is Marker Drones. Having two models doing an action every turn preventing a unit of Crisis or Stealth suits from Advancing would be quite a significant burden on the unit.

Pre-FAQ Suggested Play: Drones and Vehicles can advance and not fail the Markerlight action.


Had a lot of feedback about this and my suggestion, mostly regarding the “Move Normally” FAQ.

Move normally: Rules that refer to move/moves/moving normally are the same thing as making a Normal Move, e.g. a rule that states ‘instead of moving this unit normally’ means ‘instead of making a Normal Move with this unit’. If a rule simply tells you to make a move as if it were the Movement phase, but does not specify what kind of move is being made, it is a Normal Move.

This FAQ is probably one of the more annoying ones we currently have, as it’s very broad for what is actually a very specific issue. This FAQ is to put 8th edition abilities that just say “the unit can make a move of x” into 9th edition types. It doesn’t cause all mention of the word “move” to become “normal move”. My confidence of this fact comes from the start of the movement phase rules.

Start your Movement phase by selecting one unit from your army to move; that unit can either make a Normal Move, it can Advance, or it can Remain Stationary.

where “to move” is pretty firmly established as covering all the types of move a unit might choose to make. Fall Back as well but you have to start within Engagement Range for that and you can’t start actions while within Engagement Range so that prevents Drones and Vehicles from using the Markerlight action before falling back.

Strike and Fade on a Unit that Fell Back

So again I’m not sure about this one either; this is sort of a theme with T’au Codex issues.

Use this Stratagem at the start of your Shooting phase. Select one Tau Empire Jet Pack unit from your army. You can shoot with that unit and then it can make a Normal Move of up to 6″. That unit can not shoot again this phase.

While a unit that has Fallen Back is an eligible target for the Stratagem, whether or not the unit can shoot is definitely debatable. I’d usually expect an ability that allows Fall Back and shoot to be far more specific about it rather than “can shoot.” I’d probably lean towards “No” here by applying similar logic to the “Fight Again” abilities that say “the unit can Fight” but require the unit to actually be eligible to fight.

Some rules allow units to fight again in the Fight phase, or fight ‘as if it were the Fight phase’. Such rules cannot be used on a unit unless it is eligible to fight at the time when that rule is used. Remember that a unit is only eligible to fight if it is within Engagement Range of an enemy unit, or if it made a charge move in the same turn.

Not a perfect way to answer this; probably talk about this one pregame and check with your Tournament Organiser.

Pre-FAQ Suggested Play: This ability does not allow for fall back and shoot as it does not specifically override the fall back rule.

XV8 Crisis Battlesuit Team. Credit: Rockfish
XV8 Crisis Battlesuit Team. Credit: Rockfish

Farsight Enclaves and Allied Worlds

Yes, this works. Gunum asked me before the review, we read the page like at least twice between us. Yes it’s weird that the Tau book essentially has “successors rules” that aren’t just entirely useless. To reiterate what you gain and lose; taking an allied world as a custom sept.

  • Loses your army access to Relics and Named Characters of that Sept (barring any special rules such as Aunshi’s).
  • Gains you their Tenet traits, Warlord Trait, and Stratagem.
  • Specifically for Farsight Enclaves, you also lose the 2 Commander per detachment rule, but you also lose the no Ethereals rule. Innvocations only don’t work on actual Farsight Enclaves so your custom Sept can benefit from them just fine.


Positional Relay – what does it actually do?

Seen a lot of confusion about this one. Some of it from me. Having read it a few more times though I’m pretty confident about what it does.

Once per battle round, when you setup a friendly <SEPT> Strategic Reserves unit, the bearer can us this wargear item. If it does, that unit counts the battle round number as one higher than the current battle round number for the purposes of determining where it is set up, but when doing so it must be within 6″ of the bearer.

So this does not allow Strategic Reserve units to ignore the turn 1 limitation, because the timing of it is “when you set up” one; which you need to be able to do before triggering this rule. Once triggered though in Turn 2 you essentially get to deploy from any battlefield edge other than your opponents, as you would in Turn 3. With the limit that the place you pick has to be within 6″ of the bearer of the Positional Relay.

Gun Drones. Credit: Rockfish
Gun Drones. Credit: Rockfish


Drones do a lot and interact with the rules in a bunch of weird and inteesting ways. I’ll try to cover the main ones here.

Look Out Sir, Unit Toughness, Starting Strength and Morale

Drones now have two special rules called Valued Sacrifice and Artificial Helpers that between them cause Drones to be ignored for a few different rules interactions;

  • Morale. Each time a Drone model is destroyed, it is ignored for the purpose of Morale Tests if the unit has any models without the Drone keyword.
  • The Look Out, Sir rule. In practice this means a few things. Drones don’t contribute to the model count of units for Look Our Sir, so 1 Fire Warrior and 2 Drones doesn’t count as a unit of 3+ models for protecting characters. It also means that Drones don’t count when checking for nearest unit, you need to measure to the nearest none-Drone in a unit to see if the Character is nearest. An additional important point is that Look Out, Sir does not require every model in a Character unit to be Character for you to not be able to target that unit, just to “contain any CHARACTER models”, so bringing Drones along with a Character doesn’t suddenly make them much easier to shoot!
  • Determining this units Starting Strength, and whether this unit is Below Half Strength. Essentially Drones don’t hamper Morale fully. However their deaths still count as models lost from a unit for making the checks in the first place. Just if you fail a check on a unit of 3 Crisis Battlesuits that started with 6 Drones then being under Half Strength is having only 1 Crisis Battlesuit remaining, regardless of Drone count.
  • Determining this units Toughness Characteristic, it is also contains models without the Drone keyword. You just ignore them and use the Toughness of the model they are with. So no T4 Fire Warriors or T4 Ghostkeels, thankfully.

Saviour Protocols and Mortals

The new Saviour Protocols stratagem does not intercept the attack as it used to at all.

Use this stratagem in any phase, when a saving throw is failed for a model in a <SEPT> unit from your army. Select one friendly <SEPT> DRONE model within 3″ of that unit, or within 6″ of that unit if contains a model equipped with a drone controller. That Drone model is destroyed and the Damage Characteristic of that attack is changed to 0.

This no longer causes the attack to be allocated to the drone or the attack sequence to end as older implementations did, so any mortals from the attack would still hit the targeted unit. In addition any abilities that prevent damage reduction would completely negate this stratagem. You’d pay 1 CP to destroy a drone and then the damage hit the original target anyway, so maybe don’t do that.

Docked Drones

So the two things I really want to mention about docked drones are that the codex does not include a way to undock them other than the Designated tasking stratagem.

… If any of those DRONE models are docked with another model, set them up within 1″ of the model they are docked with before splitting the unit. Those DRONE models are no longer docked with that mode.

Secondly, how Docked Drones interact with No Prisoners might also not be obvious. While VEHICLE models don’t count for No Prisoners, DRONE models being destroyed do count and docked DRONE models are specifically destroyed if the vehicle dies. This is because No Prisoners is a per-model secondary, not per unit.

Interacting With Terrain

Drones interact with Terrain as if they have the INFANTRY keyword. So this means they can make use of traits such as Breachable and Scalable, as well as benefit from cover like the units they will often accompany.

Guardian Drones

Essentially rules as written these are a bit of a slow rolling nightmare. They technically work but not how anyone might expect them to.

Guardian Shield Generator: This model has a 4+ invulnerable save. Each time a ranged attack is made against this unit, an unmodified wound roll of 1-2 for that attack fails, irrespective of any abilities that the weapon or model making the attack may have.

So what I think will likely be how most people play it is that they treat the unit as having this ability each time the unit is targeted. However technically the unit loses the ability if the drone dies and the ability is per attack, so to actually run it rules as written you’d need to slow roll wounds if your opponent might remove the drone before any of the Fire Warriors. Personally I’m going to be suggesting that that is not intended and very tedious and instead play it as if it said this.

Pre-FAQ Suggested Play

Guardian Shield Generator: This model has a 4+ invulnerable save. If a unit containing this drone is chosen as a target for an attack, then when making that attack an unmodified wound roll of 1 or 2 always fails, regardless of any abilities.

This wording would mean that ability sticks around until the shooting unit finishes it’s attacks, regardless of when the drone is removed because you target all your attacks before resolving any, this removes the need for slow rolling. Of course this is only my suggestion but I think it’s how players would have thought the rule worked regardless.

Drones in other Units and FLY

“But Vrekais” you might be saying. Hasn’t this been fixed why talk about it now? So I want to discuss it because GW haven’t fixed all of it. There’s still a whole pile of weird stuff to do with the FLY keyword and Drones.

What have they fixed?

Q: If a unit contains both Drone models (which can Fly) and models which cannot Fly – like Pathfinders – can the whole unit move as if it can Fly (e.g. can Pathfinder models move over other models as if they were not there when moving, just because there is a Drone model in their unit and therefore that unit has the Fly keyword)?
A: No. Only the models that actually have the Fly keyword can move using the Flying rules (e.g. in a Pathfinder Team unit, only Drone models in that unit can move over other models as if they were not there when that unit makes a move).

So they’ve said that only Flying models can move as if they have FLY, they’ve said this in an FAQ answer rather than actually change the rule but despite this now contradicting the Core Rule it’s specific and it makes sense. It is a contradiction though, and this will matter later so let me demonstrate this.

If a unit’s datasheet has the FLY keyword, then when it makes a Normal Move, an Advance or it Falls Back, its models can be moved across other models (and their bases) as if they were not there, and they can be moved within Engagement Range of enemy models. In addition, any vertical distance up and/or down that they make as part of that move is ignored. However, these models cannot finish their move either on top of another model (or its base) or within Engagement Range of any enemy models.

and this rule;


Some units can include models that have different keywords. While a unit has models with different keywords, it is considered to have all the keywords of all of its models, and so is affected by any rule that applies to units with any of those keywords. If a rule only applies to models with a specific keyword, then it instead only applies to models in such a unit that have the correct keyword.

What’s still broken?

So a unit with any models with FLY is affected by any rules that affects units with FLY. We now have an FAQ that makes the movement rules an exception, however that leaves A LOT of other rules. For instance;

‘The only exception are units that can Fly, which can end a charge move within Engagement Range of an enemy Aircraft model.

Broadsides with a Drone can charge at AIRCRAFT models.

Use this Stratagem at the start of your opponent’s Movement or Charge phase. Select one enemy unit (excluding units that can FLY) within 12″ of and visible to an ADEPTUS CUSTODES INFANTRY…

They are also immune to Tanglefoot Grenades. That’s just two examples, there are more. The thing is though Drones don’t actually need FLY as much as they did in 8th edition because of this rule.

For the purposes of interacting with terrain features, DRONE models count as having the INFANTRY keyword.

This lets Drones move through terrain just like the INFANTRY units they accompany. As such here’s my suggestion.

Pre-FAQ Suggestion: Units that contain any DRONE models, other than units where all the models have the DRONE keyword, should be treated as not having the FLY keyword. Rules that specifically affect models with the FLY keyword rather than units with FLY keyword, would affect DRONES as usual regardless of if the unit is entirely DRONES or not. (e.g. A Unit of Pathfinders with a Drone model would not be treated as having FLY for the purposes of checking if it can charge an enemy AIRCRAFT unit.)

Drones in Stealth Units, can they still benefit from Camouflage Fields?

Yes. Camouflage Fields is a unit ability, it affects models in a Stealth Battlesuits Unit, drones taken with Stealth Suits are models in a Stealth Battlesuit unit.

Camouflage Fields: Each time an attack is made against this unit, subtract 1 from that attack’s hit roll. Each time a ranged attack is allocated to a model in this unit while it is receiving the benefits of cover, add an additional 1 to any armour saving throw made against that attack.

Further indications that unit abilities are useable by drones even with or without the suits remaining can be found in the Battlesuits ability.

BATTLESUIT models in this unit can make attacks with ranged weapons even when their unit is within Engagement Range of enemy units, but they can only make such attacks against enemy units that they are within Engagement Range of. In such circumstances, those models can target an enemy unit even if other friendly units are within Engagement Range of the same enemy unit.

Drones also have that ability if they’re in a unit with it, it’s just worded in such a way that they get no benefit from it because it only effects BATTLESUIT models. If Drones didn’t have this ability, there would be no need to word this rule this way. There’s no line in the ability that says the unit needs Stealth Drones, and the Designated Tasking Stratagem doesn’t create a tactical drone unit. It splits the Stealth Battlesuit unit into one Stealth unit with just DRONES, and one with just BATTLESUITS. No part of the stratagem says they lose abilities.

Use this Stratagem in your Command phase. Select one T’AU EMPIRE unit from your army that is not within Engagement Range of any enemy units and contains both DRONE models and models without the DRONE keyword. Split that unit into two units, one containing all of the DRONE models, and the other containing all of the models without the DRONE keyword.
If any of those DRONE models are docked with another model, set them up within 1″ of the model they are docked with before splitting the unit. Those DRONE models are no longer docked with that model.

This is exactly the same for Stealth infiltration abilities, or Crisis Manta Strike. It just feels odd because it persists without the Battlesuits. They certainly don’t become a Tactical drone unit because you can use that stratagem on Ghostkeels, Riptides, Pathfinders, and Fire Warriors, all of which do or can contain drones that can’t be in a tactical drone unit.

Markerlights in Engagement Range

Q: Do markerlights work in engagement range?
And more importantly, does Farsight Enclaves Markerlight rule work while in engagement range?

So the normal Markerlight action can’t put markerlight tokens onto units that are within Engagement Range of friendly units. There’s two reasons for this.


If this action is successfully completed, for each model in that unit that is equipped with one or more markerlights, for each markerlight that model is equipped with, select one enemy unit within 36″ of that model that would be an eligible target for that model if its unit had been selected to shoot, and roll one D6: on a 3+, that enemy unit gains one Markerlight token.’

and due to the Locked in Combat rule;


Models also cannot target enemy units within Engagement Range of any other units from your army – the risk of hitting your own troops is too great.

They are not eligible targets. Frequent readers might then wonder about if Vehicles such as the Skyray can do this, as units within Engagement Range of itself would be eligible due to the Big Guns Never Tire Rule. Again the answer is no, for the second reason.


You can declare a unit from your army will start to perform an action provided there are no enemy units within Engagement Range of it (excluding AIRCRAFT) and it did not Advance or Fall Back this turn.

Units can’t do actions with enemy units within Engagement Range of them.

What about Farsight Enclaves Tenet?

Each time a model with this tenet makes a ranged attack that targets a unit within 12″, the target is treated as having a Markerlight token.

Seeing as FSE units don’t need to be able to shoot at the units within 12″ or start an action for the unit to count as having a Markerlight Token there’s no reason for this tenet to stop working when they are within Engagement Range. To be clear; Markerlights still only affect ranged attacks but in a Tau army most of the units that benefit from Tenets can shoot whilst within Engagement Range.

  • Fire Warriors (Strike and Breachers) have Pulse Pistols and Stratagems to make their main weapons Pistol 2.
  • Pathfinders carry Pistols
  • Battlesuits have a rule of their own.
  • The rest have the Vehicle keyword.

The only models that can’t do this as far as I’m aware (other than Auxiliaries) are Gun Drones.


Montka and Actions 

This was the big one for Tau and it’s now been answered! Interestingly GW have decided to not alter the Montka rule though, and instead noted that this is a CORE Rules change they will be making to clarify this for the future.

Q: Can a unit that is performing an action while under the effects of a rule that lets it count as having Remained Stationary (e.g. Mont’ka) make a Normal Move without that action failing?
A: No. Any action a unit is currently performing, but has not yet completed, will still fail if that unit makes a Normal Move (or Advances, Falls Back, performs a Heroic Intervention or declares a charge), even if it is under the effects of a rule that says it counts as Remaining Stationary.

Designer’s Note: This is true for every unit in Warhammer 40,000,
and we will be adding this clarification to the next round of updates to the Core Rules, but as it predominantly affects T’au Empire players now due to the actions within their Codex, we wanted to make the answer clear to the upholders of the Greater Good ahead of time.

Happy to have that one closed off though.

Previous Answer

So this is probably the big one of the bunch and straight away I’m going to acknowledge that I think there’s a genuine gap in the rules here. For those not aware of the issue, Mont’ka lets a unit count as Remaining Stationary essentially for longer than is strictly necessary.

Each time this unit makes a Normal Move or Advances in your movement phase, until the end of Shooting phase, it count as having Remained Stationary.

By “longer than necessary” here I mean that it really only needed to say “during your Shooting phase”, and if that were the case then this whole issue wouldn’t exist.

As written though it does apparently cause a unit count as stationary from the moment it makes a Normal or Advance move. The question that follows is “does that count for not failing an Action you started at the start of the movement phase?” I don’t think it should, but I do think there’s a gap there. So with that in mind I’m going to make the suggestion that until there’s an FAQ, that Mont’ka shouldn’t be treated as preventing actions from failing. I think this is likely how a future FAQ will rule because of several of the situation ruling the opposite would allow for:

  • It would allow the Stormsurge to advance and shoot with re-rolls from their Anchor action. Which if intended need not be an action at all and could have just been a “if this unit remained stationary” rule.
  • It would mean that units such as Fire Warriors and Fireblades could Advance without failing the Markerlight action, since they’d Advance after starting the action. However Pathfinders that start the Markerlight action at the end of the phase can’t Advance because you can’t the action start after Advancing.
  • It would let Stealth-suits move and then drop their Homing Beacon, despite I think the fact that they’ve made it an action specifically to prevent this, in part because it would allow units to deep strike in very far forward on turn 1.

All of that seems unlikely to be intended to me. That’s especially because of an existing Rare Rule point under “Rules that Count as Remaining Stationary”:

Even if a unit is subject to such a rule, it cannot start an Action if it has Advanced or Fallen Back this turn.

This clearly doesn’t quite cover this case, but it is suggestive of an intent that Remain Stationary rules don’t mess with Action limitations.

Manta Strike

The ability has now been edited as suggested to require all models to have the ability to be able to use it.

Page 93 – Manta Strike
Change the first sentence to read:
‘During deployment, if every model in this unit has this ability, you can set up this unit in a Manta hold instead of setting it up on the battlefield.’

So no more Deepstriking Pathfinders or Broadsides, surfing down from orbit on their drones.

Previous Answer

So bit odd but, ALL Drones have Manta Strike. The Manta Strike ability does not have the rider that units like Death Watch got where every model in a unit need an ability to be able to use an ability.

During deployment, you can set up this unit in a Manta hold instead of setting it up on the battlefield. if you do then in the Reinforcements step of one of your Movement phases you can set up this unit anywhere on the battlefield that is more than 9″ from any enemy models.

So rules as written adding a Drone to any unit, gives them this ability. As much as Pathfinders surfing into battle on a single Gun Drone in amazing formations I think Death Watch is a pretty strong indicator of how this should work. I wouldn’t suggest trying to insist that adding a Guardian Drone to a unit of Fire Warriors gives them Deep strike just yet.

Pre-FAQ Suggested Play: Only units where every model in the unit has the Manta Strike ability can use that ability (eg. Drones in a Pathfinder unit does not allow that unit to Manta Strike).

Have any questions or feedback? Got a rules question you want answered? Drop us a note in the comments below, ask a question in our Ruleshammer form, or head over to r/ruleshammer to discuss.