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Another Tau Errata:
Smart Missile Systems have 3 different attack values.
4 shots for long strike,
3 shots for Hammerheads, Broadsides, Skyrays, and Riptides
2 shots for Devilfish

For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

 H.B.M.C. wrote:

 Dysartes wrote:
(Side note - is the Apothecary in the Command Squad really the only way to get a Proper Marine Apothecary now? Sheesh.)

Far as I can remember, the Command Squad box is the only way to get a First Born Apothecary, therefore, as everything is sprue-based options and box-based organisation, he can only therefore be in a Command Squad.

Besides ebaying for the old metals, yeah. The command box is the only thing I know of. It's maddening that they limited that unit in the way that they did, too, forcing the characters in there and leaving space for only two veterans. Strange how they give those Veterans each access to Heavy Weapons though.

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

The keywords that leaders give to their units work exactly how I predicted... Who could have predicted that.

 Slinky wrote:

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

But one they've had fairly often. And in this case a distinction without a difference. You target the unit when you make attacks. Which triggers the Anti-X

 Insectum7 wrote:

 H.B.M.C. wrote:

 Dysartes wrote:
(Side note - is the Apothecary in the Command Squad really the only way to get a Proper Marine Apothecary now? Sheesh.)

Far as I can remember, the Command Squad box is the only way to get a First Born Apothecary, therefore, as everything is sprue-based options and box-based organisation, he can only therefore be in a Command Squad.

Besides ebaying for the old metals, yeah. The command box is the only thing I know of. It's maddening that they limited that unit in the way that they did, too, forcing the characters in there and leaving space for only two veterans. Strange how they give those Veterans each access to Heavy Weapons though.

What's even funnier about that, is that the kit has an extra set of kneeling veteran legs, meaning you can build one more guy than the box indicates, arguably the only 40k kit with extra legs.

However, if we're going off box restrictions, then:

-1 Deathwatch veteran sergeant may exchange their close combat weapon for a xenophase blade
-1 deathwatch veteran may take two long-vigil melee weapons
-Proteus Kill Team Deathwatch veterans with jump packs may swap their Close Combat Weapon (Because they come with a CCW and the LVMW) for a Bolt Pistol, Plasma pistol, Flamer pistol or Grav pistol.
-Proteus Kill Team deathwatch veteran sergeant may exchange their LVMW ot CCW for a Xenophase Blade
-Proteus Kill teams may take up to: 0-5 Deathwatch Veterans with jump packs, 0-5 Deathwatch veterans in terminator armor, 0-3 (or ideally 0-5) deathwatch veterans on bike
-Fortis Kill teams may take up to: 0-5 Kill team intercessors with Plasma Incinerators, 0-5 Kill Team Intercessors with heavy bolt pistols, 0-3 Kill team Outriders
-Indomitor Kill teams may take up to: 0-3 Kill Team Heavy Intercessors with power fists, 0-3 Kill Team Heavy Intercessors with melta rifles, 0-3 Kill Team Heavy Intercessors with jump packs
-Spectrus kill teams may take up to: 0-3 Kill Team Infiltrators with bolt sniper rifles, 0-3 Kill Team Infiltrators with jump packs, 0-5 Kill Team Infiltrators with occulus bolt carbines, 0-5 Kill Team Infiltrators with combat knives
-Spectus kill team Kill team infiltrators with bolt sniper rifles may exchange their bolt sniper rifles for a Las Fusil.
-1 Spectrus Kill team Kill team Infiltrators with Occulus bolt carbine may take one haywire Mine
-A Spectrus Kill team unit that includes 1 or more Kill Team infiltrators with combat knives may take 1 grapnel launcher.
-A Spectrus Kill Team unit that includes 5 kill team infiltrators with combat knives, it may buy Reiver Grav-chutes for the unit.

Honestly, the ability to give them these absurd movement abilities might actually make me want to field a spectrus team.

FAQ

- When an ability reduces the damage by 1 and it does not specify a minimum can the damage be reduced to 0?
- How do keywords work with attached units? Does a unit of Rubric Marines all count as a Psyker for the purpose of Anti-Psyker? Are some keywords shared where others are not?
- Does Sustained Hits or other abilities from multiple sources stack?

These three FAQ questions are covered by the Rules Commentary document and therefore do not need to be sent to GW.

To add to the list:
Aeldari Storm Guardians: Models that take a Flamer or Fusion Guns have no Melee Weapon.

Breton wrote:

 Slinky wrote:

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

But one they've had fairly often. And in this case a distinction without a difference. You target the unit when you make attacks. Which triggers the Anti-X

Ok so the wraithlord that has a spiritseer join it is now a character unit of one model and thus cannot be targeted. Because as one model it has all the unit's keywords.

 Hellebore wrote:

Breton wrote:

 Slinky wrote:

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

But one they've had fairly often. And in this case a distinction without a difference. You target the unit when you make attacks. Which triggers the Anti-X

Ok so the wraithlord that has a spiritseer join it is now a character unit of one model and thus cannot be targeted. Because as one model it has all the unit's keywords.

Except there's nothing in the rules that stops you from targetting a unit with the CHARACTER keyword, just allocating a wound to a model with the CHARACTER keyword.
The unit as a collective has the keyword, but the Wraithlord individually does not.

Some Character units have ‘Leader’ listed on their datasheets. Such Character units are known as Leaders, and the units they can lead – known as their Bodyguard units – are listed on their datasheet.

Attacks cannot be allocated to Character models in Attached units.

According to the rules pdf a unit has the character rule and is also a model with the character rule.

If it wasn't then a character model wouldn't individually have the rule in the first place.

Ergo, by granting Character to the unit they join that unit is also now a character in an attached unit.

The same logic that makes the whole unit psykers applies here. You can't have it both ways.

 Hellebore wrote:

Breton wrote:

 Slinky wrote:

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

But one they've had fairly often. And in this case a distinction without a difference. You target the unit when you make attacks. Which triggers the Anti-X

Ok so the wraithlord that has a spiritseer join it is now a character unit of one model and thus cannot be targeted. Because as one model it has all the unit's keywords.

Well I was thinking the Anti-X abilites - CHARACTER has a mechanics issue - but they knew this was an issue that's why they wrote a specific exemption into Stealth requiring all models to have it.

 Hellebore wrote:

Breton wrote:

 Slinky wrote:

 Matt.Kingsley wrote:

 Hellebore wrote:
For the combined keywords thing.

Psyker makes the whole unit psyker
Character makes the whole unit character
Epic hero makes the whole unit epic hero


I'm still not clear on how a leader character giving character to their bodyguard works.

In the attached units rules it says you cannot target a character in an attached unit. If everything is a character then you wouldn't be able to target either unit?

Unit vs Model - the unit as a whole has CHARACTER because of the attached leader making it a CHARACTER unit, but the wound allocation rules are specifically about models with CHARACTER, which the bodyguard do not have. Nothing says the CHARACTER keyword (or any keywords for that matter) are transfered to models in the same unit just because the unit as a whole has them.

That's quite a confusing distinction, though

But one they've had fairly often. And in this case a distinction without a difference. You target the unit when you make attacks. Which triggers the Anti-X

Ok so the wraithlord that has a spiritseer join it is now a character unit of one model and thus cannot be targeted. Because as one model it has all the unit's keywords.

Are you getting the rules secondhand, or what?

First, that would be a two model unit. 1+1 = 2.
Second, nothing prevents attacks against a unit with a character, whether its a single character or multiple characters in a unit of 20 models.

The exception is an unattached character with [lone operative] and the attacker is more than 12" away)

During an attack resolution, you
1) roll to hit. The character keyword doesn't matter here.
2) roll to wound (_always_ against the Bodyguard (ie, non-leader) unit).
3) successful wounds are then allocated, always to the bodyguard unit unless the attack has [precision] AND the character is visible to the attacker. Without [precision], it is not possible to assign wounds to Leaders until the bodyguard unit is entirely dead. Even if the defending player wants to, it is not an option.

If the attack has [precision] the attacker can choose to assign the wound to a visible character.

4) saves now happen (unlike wounds, saves are based on the model the attack was allocated to).
5) damage is now applied.

Even with batch rolling, nothing touches the character until the bodyguard unit is dead, unless the attacker can and does assign [precision] attacks.



Automatically Appended Next Post:

 Hellebore wrote:

Some Character units have ‘Leader’ listed on their datasheets. Such Character units are known as Leaders, and the units they can lead – known as their Bodyguard units – are listed on their datasheet.

Attacks cannot be allocated to Character models in Attached units.

According to the rules pdf a unit has the character rule and is also a model with the character rule.

If it wasn't then a character model wouldn't individually have the rule in the first place.

Ergo, by granting Character to the unit they join that unit is also now a character in an attached unit.

The same logic that makes the whole unit psykers applies here. You can't have it both ways.

Read the basic attack sequence again. Anti-X doesn't matter until the wounds step. It does nothing to prevent attacks. It just changes the number at which you score a critical wound.
Wounds are still assigned to the Bodyguard unit, regardless of what you think the character keyword is doing (see the Leader ability on page 39)

One quick one. Eldar waveserpent has 4 shots for its twin star cannon, and twin linked. If going by every other twin linked weapon it can take, that should be just 2 shots.

Voss wrote:

3) successful wounds are then allocated, always to the bodyguard unit unless the attack has [precision] AND the character is visible to the attacker. Without [precision], it is not possible to assign wounds to Leaders until the bodyguard unit is entirely dead. Even if the defending player wants to, it is not an option.

If the attack has [precision] the attacker can choose to assign the wound to a visible character.

This always makes me laugh when looking at Belial's retribution style rule, or Calgar's 4++ as long as at least one Victrix is still alive.

 Hellebore wrote:

Some Character units have ‘Leader’ listed on their datasheets. Such Character units are known as Leaders, and the units they can lead – known as their Bodyguard units – are listed on their datasheet.

Attacks cannot be allocated to Character models in Attached units.

According to the rules pdf a unit has the character rule and is also a model with the character rule.

Where does that say that?
I assume you think it says that in what you quoted, but it doesn't.
Those are separate statements - there's no connecting statement that says all models in a bodyguard unit joined by a Character all gain the Character keyword, just that their unit is now a Character unit (though technically it doesn't say that there explicitly either, that's clarified in the Rules Commentary).

Again, different levels of interaction - the Unit level and the Model level.
On the unit level (which is where the targeting rules interact) - the combined Leader-Bodyguard unit has the Character keyword. Nothing generally stops you from targetting a Character unit.
On the model level (which is where the wound allocating rules interact - only the models that have the Character keyword individually (generally just the Leader(s) that joined, though Imperial Guard have a few oddities iirc) have the keyword - it is not gained by the rest of the models individually just for being in the same unit because nothing says keywords transfer on the model level, only on the unit level.

Breton wrote:

Voss wrote:

3) successful wounds are then allocated, always to the bodyguard unit unless the attack has [precision] AND the character is visible to the attacker. Without [precision], it is not possible to assign wounds to Leaders until the bodyguard unit is entirely dead. Even if the defending player wants to, it is not an option.

If the attack has [precision] the attacker can choose to assign the wound to a visible character.

This always makes me laugh when looking at Belial's retribution style rule, or Calgar's 4++ as long as at least one Victrix is still alive.

Well, given how often precision turns up (every blood sniper squad can fire entire volleys at characters as long as they can see a piece of the model, and tyranids can just make it a thing that happens for the entire army on crits), Calgar will actually get use out of the rule. Belial's is less useful, but can still happen. You just don't want to assign low damage melee attacks to him unless you have to.

Voss wrote:

Breton wrote:

Voss wrote:

3) successful wounds are then allocated, always to the bodyguard unit unless the attack has [precision] AND the character is visible to the attacker. Without [precision], it is not possible to assign wounds to Leaders until the bodyguard unit is entirely dead. Even if the defending player wants to, it is not an option.

If the attack has [precision] the attacker can choose to assign the wound to a visible character.

This always makes me laugh when looking at Belial's retribution style rule, or Calgar's 4++ as long as at least one Victrix is still alive.

Well, given how often precision turns up (every blood sniper squad can fire entire volleys at characters as long as they can see a piece of the model, and tyranids can just make it a thing that happens for the entire army on crits), Calgar will actually get use out of the rule. Belial's is less useful, but can still happen. You just don't want to assign low damage melee attacks to him unless you have to.

They have to be able to see a piece of Calgar specifically, and Belial especially... pretty much requiring a Precision Melee attack being assigned to him. Neither of these abilities are really under the controlling player's control.

Hopefully this explains the logic of what I'm saying better.

TLDR: a unit of one model with character grants character to the model in it, therefore unit keywords apply to models. You can't both protect a character from attacks with the character keyword and deny the attached unit is also all character models. There are no rules that say that only in the instance of a single model do its keywords apply to the model and the unit.


When you get to the allocation step:

If an attack successfully wounds the target unit, the player
controlling the target unit allocates that attack to one model in
the target unit, as follows.

This applies to a character unit of one model if it is alone and unattached. You assign the attack to that model (ie a farseer or a captain). The unit has character so either the model does too, so it can't have an attack assigned, or it doesn't so it can.

However if that model is a leader:

Some Character units have ‘Leader’ listed on their
datasheets. Such Character units are known as
Leaders, and the units they can lead – known as their
Bodyguard units – are listed on their datasheet.

it cannot have an attack allocated to it while attached:

Each time an attack sucessfully wounds an Attached
unit, that attack cannot be allocated to a Character
model in that unit, even if that Character model
has lost one or more wounds or has already had
attacks allocated to it this phase.

leader units add their keywords to their bodyguard unit as per

KEYWORDS
■ If a rule specifies that it applies to a model/unit with a Keyword, it
only applies to a model/unit with that keyword on its datasheet.
■ If a rule specifies that it applies to ‘non-Keyword’ models/units,
it only applies to models/units that do not have that keyword. For
example, if a rule applies to non-Vehicle units, it only applies to
units that do not have the Vehicle keyword.
■ Some units can contain models that have different keywords. While
this is the case, such a unit is considered to have all of the keywords
of all of its models, and so is affected by any rule that applies to
units with any of those keywords. Remember that attacks are made
against units, not models.

The leader rule affects the character keyword, which is now applied to the whole unit (and it specifies unit/model in the quote above).

So, a character keyword unit with the leader ability is added to another unit. All their keywords are considered combined.

When you get to the assign attacks stage, you cannot assign attacks to models with the character keyword. The rules say that a captain is a unit, with the character keyword. So he is both a model and a unit with the character keyword. They are used interchangeably throughout the leader rule.

see this quote from the leader rule:

Some Character units have ‘Leader’ listed on their
datasheets. Such Character units are known as
Leaders, and the units they can lead – known as their
Bodyguard units – are listed on their datasheet.

A character is considered a unit, so either it cant be a model with the character keyword, or a unit with keywords is also models with keywords.


So, when you attach a character keyword model, they give character to the unit and therefore the models in that unit.

And you cannot assign an attack to a model with the character keyword.


That seems logically parsimonious to me. I don't think it's what they intend, but that's what I read.

They also said that MW get divided before you apply them, which is not how the attack sequence works.

They also said that MW get divided before you apply them, which is not how the attack sequence works.

Well, no. Its how the Mortal Wounds rule works. Its an exception. When the rules call out an exception, you use that instead.


For the character stuff, you're reading selectively and piecemeal. Its really straightforward if you read it all.
You've carved it up into so many snippets its no wonder you can't make sense of it.

Voss wrote:

They also said that MW get divided before you apply them, which is not how the attack sequence works.

Well, no. Its how the Mortal Wounds rule works. Its an exception. When the rules call out an exception, you use that instead.


For the character stuff, you're reading selectively and piecemeal. Its really straightforward if you read it all.
You've carved it up into so many snippets its no wonder you can't make sense of it.

to sum it up, the game clearly shows that a unit's keywords also apply to the models in the unit.

TLDR: a unit of one model with character grants character to the model in it, therefore unit keywords apply to models. You can't both protect a character from attacks with the character keyword and deny the attached unit is also all character models. There are no rules that say that only in the instance of a single model do its keywords apply to the model and the unit.

 Hellebore wrote:
They also said that MW get divided before you apply them, which is not how the attack sequence works.

Where does it say this, specifically?

 H.B.M.C. wrote:

 Hellebore wrote:
They also said that MW get divided before you apply them, which is not how the attack sequence works.

Where does it say this, specifically?

Page 18 of the rules commentary doc:


Modifying a Damage Characteristic and Devastating Wounds Some rules modify the Damage characteristic of an attack that has the [DEVASTATING WOUNDS] ability.

■ When a rule modifies an attack’s Damage characteristic, if that attacks scores a Critical Wound, the Damage characteristic is modified before the damage is applied as mortal wounds.

 Hellebore wrote:

KEYWORDS
■ If a rule specifies that it applies to a model/unit with a Keyword, it
only applies to a model/unit with that keyword on its datasheet.
■ If a rule specifies that it applies to ‘non-Keyword’ models/units,
it only applies to models/units that do not have that keyword. For
example, if a rule applies to non-Vehicle units, it only applies to
units that do not have the Vehicle keyword.
■ Some units can contain models that have different keywords. While
this is the case, such a unit is considered to have all of the keywords
of all of its models, and so is affected by any rule that applies to
units with any of those keywords. Remember that attacks are made
against units, not models.

The leader rule affects the character keyword, which is now applied to the whole unit (and it specifies unit/model in the quote above).

So, a character keyword unit with the leader ability is added to another unit. All their keywords are considered combined.

When you get to the assign attacks stage, you cannot assign attacks to models with the character keyword. The rules say that a captain is a unit, with the character keyword. So he is both a model and a unit with the character keyword. They are used interchangeably throughout the leader rule.

see this quote from the leader rule:

So when Captain Ahab Joins Squad White Whale, they Form Super Squad Moby Dick which has INFANTRY, CHARACTER, TACTICAL SQUAD, YADDA, YADDA YADDA keywords - the Tactical Squad MODELS do NOT have the Character Keyword. But it doesn't matter because by the time that difference would matter, its already too late. So your Anti-Character 2+ wounds the ever loving crap out of Super Squad Moby Dick even though you're using the Tactical Squads White Whale's Toughness and they're not technically a character (or psychic, or a vehicle, or what have you). Given that they're trying to reduce lethality, it would be such an easy and smart move to release a FAQ that even though Super Squad Moby Dick has the Character keyword, because you're using the Toughness of Tactical Squad White Whale, you also use only the keywords of Tactical Squad White Whale to trigger the ups and downs.
Modifications are in red

Each time an attack scores a hit against a target unit, make a
Wound roll for that attack by rolling one D6 to see if that attack
successfully wounds the target unit. The result required is
determined by comparing the attack’s Strength (S) characteristic
with the target’s Toughness (T) and keywords characteristics, as shown below

While a Bodyguard unit contains a Leader, it is
known as an Attached unit and, with the exception
of rules that are triggered when units are destroyed
(pg 12), it is treated as a single unit for all rules
purposes. Each time an attack targets an Attached
unit, until the attacking unit has resolved all of its
attacks, you must use the Toughness characteristic and keywords of
the Bodyguard models in that unit, even if a Leader
in that unit has a different Toughness characteristic and/or keywords.

You probably need to tweak PRECISION as well so they can get or avoid the unit keywords when sniping

The challenge is that as per the commentary doc:

Some units can contain models that have different keywords. While
this is the case, such a unit is considered to have all of the keywords
of all of its models, and so is affected by any rule that applies to
units with any of those keywords. Remember that attacks are made
against units, not models.

the character keyword is considered one of the unit's keywords as the character model has it and applies it to the rest of them.

What this is clearly, is that they want psyker units to make their bodyguards psyker and that's it.

It would probably have been simpler for them to say:

leader units in attached units do not combine their keywords except if it is the psyker keyword.

There's no other reason for it.

 Hellebore wrote:
The challenge is that as per the commentary doc:

Some units can contain models that have different keywords. While
this is the case, such a unit is considered to have all of the keywords
of all of its models, and so is affected by any rule that applies to
units with any of those keywords. Remember that attacks are made
against units, not models.

the character keyword is considered one of the unit's keywords as the character model has it and applies it to the rest of them.

What this is clearly, is that they want psyker units to make their bodyguards psyker and that's it.

It would probably have been simpler for them to say:

leader units in attached units do not combine their keywords except if it is the psyker keyword.

There's no other reason for it.

I'd say even that's not a reason for it. The Cortosis Ore Sword doesn't slice through storm troopers just because they're standing next to Darth Vader.

It is an overall rule that could have a results due to any of the keywords that the Attached unit possesses. Psycher is the most common instance of this, but there are others. Have your Winged Tyranid Prime lead either type of Tyranid Warriors units then the Attached Unit has the Fly keyword and is thus a valid target of Anti-Fly weapons.

Katellan Robots gaining Infantry when a Datasmith is attached to them is an interesting choice.

A bunch of Sternguard shooting now INFANTRY Kastelan Robots joined by a Datasmith is... exactly what we're talking about.