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Gert has pretty much made the case I was going to. If a significant sapient population exists on a given world, then chances are that the sapient species is the one that's most likely to meaningfully resist the hive fleet's attempts to consume the planet. Plus, a human might report/cull a freaky mutant grox, but a grox isn't going to report/cull a freaky baby human.

As for hypothetical 'stealers landing on a jungle world without sapient life... I could see them going around infecting the local animal populations. However, given the seemingly highly-psychic nature of the transformation from 'stealer to patriarch and the highly-psychic nature of the artefacts made from/by the patriarch and its lair, I kind of get the impression that a patriarch can only act as a beacon to the hive fleet once it has enough extra psychic energy coming in from its followers.

So with that in mind, maybe non-sapient minds just tend to not have very strong psychic presences and thus trying to become a beacon via the worship of birds and tigers might be a lot less efficient than becoming a beacon via the worship of humanoid hybrids. Maybe even impossible.

Also, it does seem like there are limits on what kinds of species 'stealers can infect. We know that rats are still a thing in the 41st millenium. If they could, you'd think that 'stealers would infect a rat population so they could speed-run the process of creating new generations of purestrains, if only to then go on to corrupt more humans.

Also: Do note that catachan devils are (at least theorized to be) "wild tyranids" that evolved after losing touch with the hive mind. So in that particular case, it may not be possible to take control 'devils by virtue of them already be 'niddy in nature.

I'm not sure why it seems surprising that the genestealers would be able to instinctively differentiate between things that they can mate with (intelligent things with at least some psychic potential) and things that they should eat.

Genestealers going dormant when in a situation with no intelligent potential breeding material the situation of genestealer infestations on space hulks--the activity of psychic creatures stirs them out of their dormancy.

I think it's also likely that the idea that genestealers are being used to scout out food sources is wrong. The lifecycle described for them is something that's useful for scouting out -competition-, weakening that competition and drawing the hive fleet's attention. It's sort of pre-digestion of psychic races. Hive fleet wouldn't need any help dealing with an uninhabited feral planet, after all.

For me, it’s about the availability of sentient species.

Where there is one present, it of course makes sense for the Genestealers to go after them, even just from a survival point of view.

But where there isn’t? They have to make-do with whatever it is they have at claw. Because their purpose is to scout now biomass and then bring in a Hive Fleet. That by no means requires sentient species to be present.

As I argued above, there is sense in them doing what they do wherever they end up. A world teeming with Biomass, but nothing that would offer resistance? That’s pretty ideal for a Hive or Splinter Fleet in near starvation mode that needs to replenish itself.

As for background representation? Remember it’s all very Imperiumcentric by default. But the Imperium though staggeringly vast is far flung and disparate. There are many, many worlds yet to be discovered - not just by mankind, but because the Galaxy is so vast, potentially undiscovered by anyone. I appreciate this bit is Unfalsifiable, but I promise I’m using it in Good Faith.

Essentially if there’s no sentient species, or at least Warp Capable but otherwise fairly advanced sentient species to like….notice? Who’s going to know?

I suspect it would be rare though. As noted Genestealers have limited options when it comes from getting from A to B. They either need to be sent on a journey by an established Cult, or hitch a ride with whatever interstellar ships they can. So the circumstances needed for one or some to end up on such a hypothetically undiscovered world are…pretty unique and unlikely.

The most likely of course would be Space Hulks. Those drop in and out of the Warp seemingly at random, and so may pop out near such a world. But even then, the Genestealer(s) still need to get planetside. An escape pod could well do it, but the question then becomes would they exit hibernation without other triggers, such as a boarding party ringing out the mental dinner bell.

Mind you…how did Genestealers get here ahead of the Hive Fleets in the first place? I’m envisaging something akin to the Probot’s from ESB. Long range, warp capable seed beasts with a handful of Genestealers - but again that’s just speculation.

Tsagualsa wrote:

Spoiler:

 Irbis wrote:

 NapoleonInSpace wrote:
The dairy farm, OTOH? Its equally well organized, and if the farmer, the bull and the cows are all infected, who's really going to notice? The farmer's wife, kids and neighbors? Probably not. They're not on the lookout (at least not beyond the level of typical Imperial superstition) at anywhere near the level the commissariat is. And the cows would do exactly what cows do. Breed. No one would question their actions. And, to the best of my understanding, genestealers go through for generations of getting more like the host race in appearance, and then breed a new purestrain stealer.

Actually, meat and milk of our herds is so painstakingly purified and analyzed even today (to the point absolute sterility of milk famously started making Swiss cheese go bad and Swiss scientists had to figure out artificial dirt to make it mature properly again - and no, this is not a joke) that any sort of alien taint would be noticed immediately. I'd bet Imperium does so too seeing fresh meat and produce is something reserved for elites. Ironically, dairy farm might be the hardest to corrupt installation on any given Imperial planet. So why bother when local village population is much easier target (though funnily enough, said cult would probably need to become the cleanest part of the planetary demographic observing harsh hygiene regime so their hair, dead skin cells, etc, didn't make it to raw food as that might be picked up by above analysis too)...

Not only that - which is an excellent point - but there are other factors in commercial livestock farming that would present dead-ends for genestealers. Parent animals and offspring are routinely separated. Male animals are usually either killed or castrated before they reach sexual maturity. Conventional insemination is rare, artificial insemination more common. So your whole cycle of hybridization would have real problems to get of the ground, as most of your male first-generation hybrids would be slaughtered before they could reproduce, and even if they could they would get no access to female animals to do it. That all depends on the set-up obviously, if you got free-running herds like in the old west it would work out differently, although even then the breeding bulls tended to be specially selected. Cowboy inquisitors coming up against genestealer-related cattle-mutilitians would be one hell of a setting for a story though

I think this would be true for grox farming too. Wild grox are vicious predators, so farmed grox are routinely lobotomised, suggesting a high degree of oversight and intervention. Frequently, some members of the herd are also turned into defence servitors with automated anti-intruder las weaponry.

 Wyldhunt wrote:
So with that in mind, maybe non-sapient minds just tend to not have very strong psychic presences and thus trying to become a beacon via the worship of birds and tigers might be a lot less efficient than becoming a beacon via the worship of humanoid hybrids. Maybe even impossible.

You'd think Hive Mind would plan for that eventuality and included the DNA sequence for mass creation of beacon "patriarchs" if a Genestealer happens to land on biomass rich world with OK host species but no intelligent/psychic ones. In fact seeing such worlds should be the vast majority of them (just look at Earth, 3 billion years old life but real sapience is only found in last 200.000+ years) it would be dumb for Hive Mind to not have plan for that.

Also, it does seem like there are limits on what kinds of species 'stealers can infect. We know that rats are still a thing in the 41st millenium. If they could, you'd think that 'stealers would infect a rat population so they could speed-run the process of creating new generations of purestrains, if only to then go on to corrupt more humans.

I'd imagine the only limit is the size of species. Can the species in question give birth to infant Genestealer? If yes, infectable, if not, mind control with a Kiss is the best they can do.

 solkan wrote:
Hive fleet wouldn't need any help dealing with an uninhabited feral planet, after all.

Yes, but finding said planet and tagging it on the 'map' is another matter, and logically, something in Tyranid swarms should be looking for them. Genestealers just seem obvious fit for the job seeing they do scouting for prey anyway.

Sapient species represent opposition to the Hive Mind which much be neutralized.

Regular animals are a food item.

They are categorically different, so would trigger different behavioral reactions in Tyranid organisms. Tyranids, even the Hive Mind, don't exactly sit and weigh the merits of alternate strategic approaches. Otherwise they would have realized the exponential biomass generation capability of farming choice worlds instead of consuming them and likely have 'won' the setting a long time ago!

To put more simply; giving an ant swarm gestalt intelligence and hyper adaptation does not teach it the merits of sustainable agriculture.

a

 NinthMusketeer wrote:

They are categorically different, so would trigger different behavioral reactions in Tyranid organisms. Tyranids, even the Hive Mind, don't exactly sit and weigh the merits of alternate strategic approaches. Otherwise they would have realized the exponential biomass generation capability of farming choice worlds instead of consuming them and likely have 'won' the setting a long time ago!

That's not how biomass works, planets have a very limited amount of biomass they can support as they only get so much energy from the sun and have limited amounts of nutrients in their soil, and tyranids routinely outproduce that (you aren't growing a continent sized bio-ship on sustainable agriculture).

 Tyran wrote:
a

 NinthMusketeer wrote:

They are categorically different, so would trigger different behavioral reactions in Tyranid organisms. Tyranids, even the Hive Mind, don't exactly sit and weigh the merits of alternate strategic approaches. Otherwise they would have realized the exponential biomass generation capability of farming choice worlds instead of consuming them and likely have 'won' the setting a long time ago!

That's not how biomass works, planets have a very limited amount of biomass they can support as they only get so much energy from the sun and have limited amounts of nutrients in their soil, and tyranids routinely outproduce that (you aren't growing a continent sized bio-ship on sustainable agriculture).

Yeah, the biomass on a planet with life generally won't change much at all. It just gets recycled endlesslly.

Biomass's technical definition is the total mass of living organisms, but at an even more basic level that the tyranids care about is that it is carbon. Specifically bioactive forms of carbon, along with trace minerals.

Really the only way to create new biomass is to find elemental carbon and get it into a food chain.


In theory, the tyranids could do this just be scouring the galaxy looking for carbon deposits then using solar radiation and photosynthesis break it down into usable forms. Essentially have fully functioning ecosystems aboard their hive ships with no real need to continue spreading other than the desire to reproduce.

But why do the hard part of making your own biomass when you could just steal it...

 Tyran wrote:
The hybrids definitely would be dumber.

Also the point of a Genestealer infestation isn't to put up a resistance, but to undermine the local defenses when the Hive Fleet arrives. A Genestealer cow isn't infiltrating the local government.

The local government doesn't drink milk?

[BTW, sorry for seemingly abandoning this thread. I had to work this weekend and got a nasty cold on top of it]


Automatically Appended Next Post:

 Wyldhunt wrote:

Also: Do note that catachan devils are (at least theorized to be) "wild tyranids" that evolved after losing touch with the hive mind. So in that particular case, it may not be possible to take control 'devils by virtue of them already be 'niddy in nature.

Never heard that. Very cool.


Automatically Appended Next Post:

 solkan wrote:


I think it's also likely that the idea that genestealers are being used to scout out food sources is wrong. The lifecycle described for them is something that's useful for scouting out -competition-, weakening that competition and drawing the hive fleet's attention. It's sort of pre-digestion of psychic races. Hive fleet wouldn't need any help dealing with an uninhabited feral planet, after all.

I get the idea. But even nids have to get old and die at some point. What happens when they enter a section of space where sentient life just doesn't exist? Do they all go dormant?


Automatically Appended Next Post:

 Mad Doc Grotsnik wrote:
For me, it’s about the availability of sentient species.

Where there is one present, it of course makes sense for the Genestealers to go after them, even just from a survival point of view.

But where there isn’t? They have to make-do with whatever it is they have at claw. Because their purpose is to scout now biomass and then bring in a Hive Fleet. That by no means requires sentient species to be present.

As I argued above, there is sense in them doing what they do wherever they end up. A world teeming with Biomass, but nothing that would offer resistance? That’s pretty ideal for a Hive or Splinter Fleet in near starvation mode that needs to replenish itself.

As for background representation? Remember it’s all very Imperiumcentric by default. But the Imperium though staggeringly vast is far flung and disparate. There are many, many worlds yet to be discovered - not just by mankind, but because the Galaxy is so vast, potentially undiscovered by anyone.

I just don't see an argument against that ^^

 NapoleonInSpace wrote:

The local government doesn't drink milk?

If your plan is to contaminate the food and water supply, sapient hybrids are better at that.

Excellent discussion, gents, and I really appreciate all viewpoints. A lot of this is DEFINITELY going in my next 40k rpg campaign.

That said, I think a point that has gotten lost here is that Tyranids can make their space vessels as easily from the dumbest grox to the super-dumbest one celled life form to Leonardo DaVinci, St. Augustine, Gottfried Leibniz and Bill Gates. In the end, biomass has to be biomass to them.

Now, I can see the argument that, given the choice between a high tech world that is, or at least can gear up to be, heavily armed, had better be taken out before a jungle planet, but if the one is not present and the other is, why wouldn't they just chow down and replenish the fleet?


Automatically Appended Next Post:

 Tyran wrote:

 NapoleonInSpace wrote:

The local government doesn't drink milk?

If your plan is to contaminate the food and water supply, sapient hybrids are better at that.

Granted, but ya go with whatcha got in some circumstances.

 NapoleonInSpace wrote:


Now, I can see the argument that, given the choice between a high tech world that is, or at least can gear up to be, heavily armed, had better be taken out before a jungle planet, but if the one is not present and the other is, why wouldn't they just chow down and replenish the fleet?

They do, but it's not very interesting from a wargaming point of view, so it's relegated to the general background and seldom the focal point of stories or books. You could write a good story about e.g. a team of Biologis on a remote planet witnessing all of that, but so far GW hasn't done so as far as i'm aware. It would be nice for a RPG campaign too, but you see how you have to start to make plot contrivances and just-so coincidences to even have people, let alone armies present for it. Just like the Exodites with their core goal of being left the feth alone, they do not lend themselves to being present in any given battle in the galaxy easily.

 NapoleonInSpace wrote:
The local government doesn't drink milk?

The local government isn't going to be eating or drinking anything that hasn't been thoroughly checked by their servants first, and that includes bio scans. 40k has a lot more ways to kill people with poisons and the like and local leadership often don't get their positions without making powerful enemies. Xenos mutations pop up pretty quickly in these sorts of things.
It's easier to actually get Cultists to infiltrate the household staff than it would to serve tainted produce.

I get the idea. But even nids have to get old and die at some point. What happens when they enter a section of space where sentient life just doesn't exist? Do they all go dormant?

Yup, Genestealers go into hibernation and just wait until something comes along. One of the reasons Space Hulks are so dangerous is because entire hives of Genestealers will hibernate on them just waiting to drop into a system where they can begin infecting the locals.

Tsagualsa wrote:

 NapoleonInSpace wrote:


Now, I can see the argument that, given the choice between a high tech world that is, or at least can gear up to be, heavily armed, had better be taken out before a jungle planet, but if the one is not present and the other is, why wouldn't they just chow down and replenish the fleet?

They do, but it's not very interesting from a wargaming point of view, so it's relegated to the general background and seldom the focal point of stories or books. You could write a good story about e.g. a team of Biologis on a remote planet witnessing all of that, but so far GW hasn't done so as far as i'm aware. It would be nice for a RPG campaign too, but you see how you have to start to make plot contrivances and just-so coincidences to even have people, let alone armies present for it. Just like the Exodites with their core goal of being left the feth alone, they do not lend themselves to being present in any given battle in the galaxy easily.

Well, that is pretty much the setting for Imperial Armour 4: The Amphelion Project.

Three individual Tyranids under study eventually spawned a horde incl. biotitans that overwhelmed the bases and the forces sent to investigate after they went silent.

 NapoleonInSpace wrote:


Granted, but ya go with whatcha got in some circumstances.

I don't disagree with the idea that if a Genestealer finds itself in a world devoid of civilization, it will likely infect the apex predators or something.

I just don't see the benefit when there is a civilization present.

 NapoleonInSpace wrote:


I get the idea. But even nids have to get old and die at some point. What happens when they enter a section of space where sentient life just doesn't exist? Do they all go dormant?

Says who?

When you have total control over your biology down to the cellular level you can just regenerate any age related degeneration. On Earth today there are a few select species which are suspected to be functionally immortal due to some regenerative techniques that repair degeneration of their DNA caused by age. Its pretty rare, but Tyranids can just do that on purpose with the organisms that need it.

So the only limiter becomes food. And nids definitely go dormant when there is a lack of it. Genestealers are the exact example of this.


Automatically Appended Next Post:

 Tyran wrote:

 NapoleonInSpace wrote:


Granted, but ya go with whatcha got in some circumstances.

I don't disagree with the idea that if a Genestealer finds itself in a world devoid of civilization, it will likely infect the apex predators or something.

I just don't see the benefit when there is a civilization present.

There wouldn't be any reason unless the sentient species present was for some reason immune or inaccessible to the genestealers. Perhaps the only sentients present are a highly psychic race and can just see the genestealer coming or easily detect and eliminate any infected members of their species. Orks kinda fall into that category, Genestealer orks are just "unorky" to the other orks.

 Haighus wrote:

Tsagualsa wrote:

 NapoleonInSpace wrote:


Now, I can see the argument that, given the choice between a high tech world that is, or at least can gear up to be, heavily armed, had better be taken out before a jungle planet, but if the one is not present and the other is, why wouldn't they just chow down and replenish the fleet?

They do, but it's not very interesting from a wargaming point of view, so it's relegated to the general background and seldom the focal point of stories or books. You could write a good story about e.g. a team of Biologis on a remote planet witnessing all of that, but so far GW hasn't done so as far as i'm aware. It would be nice for a RPG campaign too, but you see how you have to start to make plot contrivances and just-so coincidences to even have people, let alone armies present for it. Just like the Exodites with their core goal of being left the feth alone, they do not lend themselves to being present in any given battle in the galaxy easily.

Well, that is pretty much the setting for Imperial Armour 4: The Amphelion Project.

Three individual Tyranids under study eventually spawned a horde incl. biotitans that overwhelmed the bases and the forces sent to investigate after they went silent.

Sounds very cool! Got a link?


Automatically Appended Next Post:

 Gert wrote:

 NapoleonInSpace wrote:
The local government doesn't drink milk?

The local government isn't going to be eating or drinking anything that hasn't been thoroughly checked by their servants first, and that includes bio scans. 40k has a lot more ways to kill people with poisons and the like and local leadership often don't get their positions without making powerful enemies. Xenos mutations pop up pretty quickly in these sorts of things.
It's easier to actually get Cultists to infiltrate the household staff than it would to serve tainted produce.

Mmmm... No. Not, at least, as I understand the Imperium.

Granted, there will be high tech worlds and very rich worlds, where such technical resources exist, but by and large, the Imperium is a ramshackle mess of hiveworlds, worlds with largely medieval standards of living, and worlds plunged constantly into at least guerilla warfare.

Are such niceties likely to be found in those places?

Even on Earth, there are enormous undercities where the law of the Imperium seldom touches. When it does, of course, it does so with efficiency and brutality, but more often, the city scum clear out when they get word that the Inquisitors or the Custodes are on the way. My take, anyhow.


Automatically Appended Next Post:

 Tyran wrote:

 NapoleonInSpace wrote:


Granted, but ya go with whatcha got in some circumstances.

I don't disagree with the idea that if a Genestealer finds itself in a world devoid of civilization, it will likely infect the apex predators or something.

I just don't see the benefit when there is a civilization present.

Oh, don't get me wrong! I quite agree!

But those situations must be fairly common. My thought, anyway.

To the original question, the short answer is not to think about it too much. Like most things when dealing with the tyranids, if you think about it too much, the whole set up for their behavior tends to fall apart.

Lore wise, the reason genestealers don't (usually) infect the biosphere might just be that they require a certain degree of sapience for the strongest of the original brood to evolve into a patriarch.

Assuming that they can't breed normally, a single brood of genestealers is all there will be until they infect a population who then spends generations breeding until they start spawning purebreds usually right as a planet is ripe for eating. Though funnily enough, a genestealer cult can survive longer than the initial infecting brood, since in the early stages of the octavius war, the Kryptman's original gambit brood of genestealers was eventually killed off by the orks.

Another possibility is that the subject species must have at least some form of warp shadow to be considered a viable candidate for assimilation. We know that genestealer cults are susceptible to psychic discordance--in one comic, a genestealer cult of orks and humans team up and can't coordinate for gak because they're behaving on different frequencies from the patriarch.

The thing to remember about tyranids and genestealers is that they aren't a single species. They aren't even composed of separate species working towards the same goal. It's a single mega-organism and each strain has its job--and that job is usually not the proliferation of the species. Genestealers infect and breed not as the sole drive to continue their genetic line but because its a byproduct of their true functions which is to identify and subvert so a hive fleet can come by and have an easier job slurping up a planet. Remember, even when a hive fleet is victorious, it kills every living thing on the planet, including its own forces that it disgorged to conquer it because it's easier to pump the raw biomatter up through capillary towers than it is to lift individual creatures back up.

 NapoleonInSpace wrote:
Mmmm... No. Not, at least, as I understand the Imperium.

Granted, there will be high tech worlds and very rich worlds, where such technical resources exist, but by and large, the Imperium is a ramshackle mess of hiveworlds, worlds with largely medieval standards of living, and worlds plunged constantly into at least guerilla warfare.

Are such niceties likely to be found in those places?

Even on Earth, there are enormous undercities where the law of the Imperium seldom touches. When it does, of course, it does so with efficiency and brutality, but more often, the city scum clear out when they get word that the Inquisitors or the Custodes are on the way. My take, anyhow.

Not amongst the wider civilian population but we're talking about the upper classes who wear dresses held up by servo skulls and hats with laser designators. The chances of them eating from their own world is pretty low enough let along anything that hasn't been tested for every known poison, toxin, and danger.
And if the Genestealers are going through the effort of tainting the food supply, it's just easier and far more effective to infect the actual people in the first place. Why bother going through the cycle with a less evolved species that is far more likely to be discovered as tainted and mutated when there is a more evolved species that has huge areas of its society underdeveloped, unwatched, and uncared for? Not only is there the political aspect when the Cult attracts members who aren't infected but the local Enforcers aren't going down to the bottom of a Hive because some new religious group has a penchant for baldness.

 Grey Templar wrote:
I'm sure a Genestealers can infect lower lifeforms, but it isn't the goal and would probably be a deadend for the genestealer that did it.

What do you mean by this? these aren't bees, a Genestealer infecting a lower lifeform can still go on to infect other things, where does the "deadend" come into it?

To me the answer seems obvious - Genestealers can and do infect native species (nothing in any description of the process is contingent on a sapient host), but it either happens in such small numbers, or the cult rarely develops far enough to be represented on the tabletop, and none of the authors find the concept interesting enough to write about. If something should exist in the 40k universe but is never written about or described, then to what extent does it exist?

Charax wrote:

 Grey Templar wrote:
I'm sure a Genestealers can infect lower lifeforms, but it isn't the goal and would probably be a deadend for the genestealer that did it.

What do you mean by this? these aren't bees, a Genestealer infecting a lower lifeform can still go on to infect other things, where does the "deadend" come into it?

Yes, but if there were better things to infect then the Genestealer would be infecting them instead.

It implies that the genestealer only has lower lifeforms to infect and start a cult with. This will result in extremely unintelligent broods, compared to normal anyway(they'd be smart for animals). So it is a deadend in the sense that the genestealer can't fully perform its main function. The brood might even be less controllable than normal because they are just base animals, meaning that there won't be careful breeding over the generations so they may not even be able to complete the genestealer lifecycle(get back to purestrain genestealers).

That is how it kind of ends up being a deadend. You end up with hybrids that are largely useless and more difficult to control.

I don’t agree it prevents their main goal. The goal is to suss out and guide a Hive Fleet to centres of Biomass.

Once any Cult grows to a (currently poorly defined) sufficient size, the Patriarch sends out the psychic signal which will attract a Hive Fleet.

Now, if the Cult is on a world where they’ve infiltrated a sentient species? Yes the Cult’s activities will likely have done some damage to if not entirely overthrown the defence forces, giving the Hive Fleet an easier meal than just rocking up and hoping for the best.

But even if there is no sentient species? A meal is a meal - and it’s one the Hive Fleet might meet zero resistance in consuming. Even if it takes the Cult longer to get to the size where the signal is generated.

So there absolutely is a gain there, even if the situation isn’t playing to the full potential of a Genestealer Infiltration.

Is that description of the gene stealer's main goal "fact" or the Imperium's leading theory?

Because the hive fleet probably doesn't need any help consuming a planet of non-sentient animals. And I forget which thread it was in, but there was a comment about the Imperial observers saying that the hive fleet was becoming a picky eater after nearly completely stripping worlds in their earliest encounters.

And building on the "picky eater" observation... gene stealers finding sentient races, disrupting them by forming gene stealer cults, and directing the hive fleets to those worlds fits the *Kill off the local competition, and then eat the rest at your leisure". Because I'm sure everyone agrees that those randomly buzzing around Eldar and Space Marines and other races are annoying, especially when they interrupt a meal.

That's what the tyranids gain from having picky scouts: They're saving the easy stuff for a leisure dessert banquet.

Trouble there is we don’t tend to see Purestrains having a great deal of choice in where they end up.

Yes established Cults are pretty adept at smuggling Purestrains aboard ships to infest new worlds. But, an already isolated Purestrain just has to cross its claws and hope it arrives somewhere useful.

The upside of that of course is anything which might let them get from Planet A to Planet B is most likely to be a spacecraft. But accidents happen. A relatively small merchant craft could suffer a catastrophe, and crash into a planet, killing the crew. Genestealer ends up stranded, giving it the opportunity to infest the local Fauna instead. Exceedingly rare, sure. But rare doesn’t mean impossible.

Plus, however the first Genestealers got here, we can’t simply assume the Hive Fleets knew it would find sentient species.

 solkan wrote:
Is that description of the gene stealer's main goal "fact" or the Imperium's leading theory?

Because the hive fleet probably doesn't need any help consuming a planet of non-sentient animals. And I forget which thread it was in, but there was a comment about the Imperial observers saying that the hive fleet was becoming a picky eater after nearly completely stripping worlds in their earliest encounters.

And building on the "picky eater" observation... gene stealers finding sentient races, disrupting them by forming gene stealer cults, and directing the hive fleets to those worlds fits the *Kill off the local competition, and then eat the rest at your leisure". Because I'm sure everyone agrees that those randomly buzzing around Eldar and Space Marines and other races are annoying, especially when they interrupt a meal.

That's what the tyranids gain from having picky scouts: They're saving the easy stuff for a leisure dessert banquet.

Which might argue that the splinter fleets would change their tactics, given their reduced power and need to grab what they can where they can? Interesting.

 Mad Doc Grotsnik wrote:

But even if there is no sentient species? A meal is a meal - and it’s one the Hive Fleet might meet zero resistance in consuming. Even if it takes the Cult longer to get to the size where the signal is generated.

Failure to understand galactic scales: your oldest and closest companion. Hive fleets are not like you and your mates on a pub crawl who get a text from Jackie Boy about a BOGO chicken korma promo, and pile into an ubered Peugeot to go three blocks and take care of business. Cults wait centuries for hive fleets to show up. Cult beacons are not messages from out of the ether that completely reset a hive tendril's longterm strategic goals and dispersion.

The whole "picky eaters" speculation is meant to indicate that the Tyranids' goals, on a galactic-strategic level, have shifted from maximal intake to steady upkeep in service of their ultimately mysterious objectives.

I'm basically with Tyran; there's no reason *not* to do a little light infection if a Genestealer ends up on a wilderness world, but it's not really important or what they're designed for. On populated worlds infecting animals would just be performing a middleman phase (because the purpose of the infected animals would be to eventually infect/disorganize the sapients). It could still be an interesting conceit for a narrative, though... like a trapped and cornered Genestealer whose last ditch contribution is to infect some livestock, and then following the slowed development of the infestation/cult through the vector of the livestock industry.

Livestock is kinda terrible at making cults. An infected cow isn't going to be smart enough to know it has to hide its hybrid offspring to avoid detection. Moreover livestock exists in extremely controlled and limited conditions because otherwise that is how sanitary crises start. The livestock industry has become very good at detecting and eliminating diseases in their livestock, otherwise we would all be dead from food poisoning by now.

As far as a Genestealer is concerned, livestock is an obvious dead end and would get farther by infecting the farmer instead.

But our world is an extremely poor comparison for 40K.

We see a Terran meat-processing plant in The Carrion Throne and an Imperial food-safety inspector in Nightbleed and neither story indicates that the Imperium has high standards for those industries. Move the focus from critical hive worlds to backwater agri-planets and things can potentially get even more lax.

Even if food standards are poor, the operators of any source points are either going to notice the infection and cull their livestock for fear of the Enforcers/Arbites or they're in on it as Cultists at which point why bother with the livestock. Nobody is going to get infected with the Genestealer curse because they ate Grox/Genestealer hybrid meat. That's not how it works.

 Gert wrote:
Even if food standards are poor, the operators of any source points are either going to notice the infection and cull their livestock for fear of the Enforcers/Arbites or they're in on it as Cultists at which point why bother with the livestock. Nobody is going to get infected with the Genestealer curse because they ate Grox/Genestealer hybrid meat. That's not how it works.

We do have 'canonical' examples of both Genestealers using the food industry (by infecting the workers and using carcasses of large animals to ship dormant stealers offworld) as well as using alternative means of contagion (the Spiral Helix cult, who uses Stealer-tainted medicinal products, presumably blood products, gene therapies or grown organs) to spread the infection. These are better examples of alien cunning mixed with host-species knowledge than just cow-stealers and dog-stealers and chicken-stealers, oh my... Infected animals are an interesting oddity, but they remain a side note in a setting that ultimately deals with sapients.