Hey all, just a quick question for you Tau aficionados out there...

For a while now we've been playing a campaign of Rogue Trader, and the party's Rogue Trader is... Well, a Tau. Essentially, the character's backstory is that the Tau was a half-breed son of an ethereal and an earth caste laborer, and given the Taus strict policy in intermingling blood his earth caste mother, the leader of a Tau mining colony, decided it would be better to sell him off rather than try and raise him as a half-blood in Tau society where at best he would be a social untouchable or at worst killed (the player doesn't actually know that he is half-ethereal so I'm hoping he doesn't end up reading this, as spoilers abound - as it is he doesn't know why he was sold as an infant).

Thus, the Tau infant was adopted by a Rogue Trader named Graxis McAllister and given the name Galley Shay. Raised in the decadent lifestyle of a hedonistic pirate, Shay eventually went on to command his own ship and crew. After discovering the science of transgenic grafting, the ship's crew started to augment themselves with xenos body parts but doing so began to drive them insane. To save their minds they dedicated themselves to chaos (as Black Crusade characters don't track insanity, and their Seneschal was at a whopping 96 insanity points from something like seventeen alien surgeries).

So our Tau Rogue Trader (who now has a human stomach, ork fungus blood, and simulacrum hands) has decided it makes the most sense to align himself to Slaanesh given his love of rum, money, and charismatic persona (their home world of operations is covered with statues of him, and his ethereal genes make him well-disposed to leadership). I'm just interested as to how people would interpret a Tau dedicating himself to Slaanesh, and how that would work mechanically. In Rogue Trader it says Tau don't gain malignancies or mutations from corruption, but they still become unplayable at 100 CP, which implies they can turn to chaos, even if it's very rare. Normally Tau are predisposed against Chaos due to their culture and the attitude of the greater good, but given that Shay was raised outside of tau society those restrictions shouldn't apply to him. So far, we've been mechanically representing his corruption and infamy the same way as a normal human heretic - currently he has twenty something corruption points, with the Infernal Will and Warp Saturated mutations (meaning that he is literally leaking rum from his pores).

If anyone is interested in ways to represent Tau corruption, post!

Firstly, it makes a certain amount of sense that, bereft of the protection of Ethereal mind-control pheromones, a Tau might well be more open to corruption than otherwise (morally, at least, even if not physically). However, unless Ethereals mix physical/chemical mind control with a touch of warpy goodness, I doubt that a Tau would really be in-tune with any Chaos power, and even if he "dedicated" himself to Slaanesh I'm not sure that anyone would even notice, least of all the Misster S. All of the lore that I've seen suggests that their warp presence is about as minimal as you can get without going negative.

Of course, the first rule of 40k canon is that none of it is for sure. If you want to interpret the Tau as simply shielded from the warp by the efforts of the Ethereals, perhaps even aided in that by the Eldar, then it'd be far more feasible to have a Tau truly fall to Chaos and form a meaningful pact with the Ruinous Powers.

Could it be explained by Galley gaining a stronger warp presence as a result of not being a pure Tau anymore? For example, could the inclusion of DNA from psychically active races, such as Orks and humans, strengthen him up to a more considerable warp presence?

Firstly, it makes a certain amount of sense that, bereft of the protection of Ethereal mind-control pheromones, a Tau might well be more open to corruption than otherwise (morally, at least, even if not physically).

The idea of "mind control pheromones" doesn't really exist anywhere but in a single Black Library book, though (and FFG's Deathwatch RPG even made fun of it). In GW's own writing, it's seems to be more of a matter of their genetics -- possibly connected to the accelerated/uplifted evolution that has been hinted at in various sources:

" Blunt: All Tau have virtually no psychic presence in the Warp. To the daemon, they appear as a shifting will-o-the-wisp rather than the burning fire that represents a human's soul. As such, Tau can never have psychic powers. All daemons, daemonhosts and other denizens of the Warp attempting to detect a Tau have -50% to their Awareness rolls and must roll even when the Tau is in plain sight. If they fail this detection roll, they must act as if they had no knowledge of the Tau's presence."

-- d100 Inquisitor game

That being said, the franchise's background is pretty much based on the concept of personal interpretation, so there would be nothing wrong about going with a different idea, as long as the rest of the group is onboard with it. In this case, the sale(!) of a Tau child into the hands of a travelling entrepreneur of an alien species known for its aggression and lack of morality (from Tau PoV) is already pretty far out there, so I'd say there's no reason not to continue down that path a little further if the player really wants to partake in the fun of mutation.

The aforementioned transplantation of alien limbs would certainly make for a convenient justification, especially if he truly implanted Ork organs, of all things. After all, Orks are more fungus than animal, and they don't actually "die" just because you cut something off -- the spores remain active, so you could well argue that the implanted limb would have taken on a life of its own. And since the franchise has featured Chaos-corrupted Orks before ... I'd say that could be your hook.

Ah, see we've always treated Xenology as canon so that's where we got the idea for the mind-control pheromones - similarly, we use the Oldcron fluff from before the Wardian rewrite, and most of the tone of our games plays off of some of the early-installment weirdness of Rogue Trader (the first edition of WH40k, not the FFG Rpg). Espeically given the appearance of the Qu'orl in Dark Heresy and Deathwatch, a race that may have originally had the "diamond Organ" that generates the pheromones and makes the Tau so warp-resistant. Which begs another question - given that the Rogue Traders employ simulacra surgeons with a wealth of experience in alien biology, could they feasibly remove this diamond organ to grant Galley back his warp-presence? In xenology, it's heavily implied that the Eldar removed that organ from the Qu'orl and implanted it into the Tau to create a race more resistant to warp corruption and psychic infections such as psychnienin, so if need be they could feasibly remove it to give Galley a full soul.

As for the sale of the Tau infant into the hands of the Rogue Trader, the player himself didn't give me an explanation as to why he was sold, only that he was. In my mind, if a Tau parent knew their child would be faced with death upon discovery, it may make sense to sell the child to a human? I agree though the Tau have a dim view of the Imperium, especially rogue Traders - if there are any other circumstances you could think of that would make this transaction make more sense, I would love to hear them, as I'm planning on having the Rogue Traders encounter Galley's mother at some point in the future - perhaps she was blackmailed into it somehow by Galley's surrogate father? Although I'm not sure what burning motivation he would have to acquire a Tau infant. Which brings up the question as to how she would react when faced with a hulking, rum-leaking, half-Ork half-Tau abomination?

Essentially, in the Radical's Handbook there are instructions for a procedure for transgenic grafting, in which the surgeon makes a -30 Forbidden Lore (Xenos) Test and a -30 Forbidden Lore (Warp) Test, with failure on either resulting in either Insanity gain or mutation. Galley has actually turned this into a rite of honor aboard his ship - the first member of any species to die in a boarding action has a commemorative statue of them made and a part of their body grafted onto the captain so that they can live on through him. So far, he has taken an human stomach so that he could actually digest meat (which failed, but he gained the Necrophage mutation which functions similarly), the Ork's 'Ard trait (+20 to Medicae Tests to apply first aid, as well as a number of talents like Iron Jaw), and simulacra hands for Ambidextrous. I like your idea that the fungus could have developed its own sentience - I never would have thought of that!

Also, thanks for not immediately going "It's not canon, it can't happen."

Ah, see we've always treated Xenology as canon

Does that mean your Orks have green blood, too?

Joking -- I actually like Xenology from a story perspective; it's told in a way that is fun to read and I dig the scribbles and pictures. It's unlucky that much of it doesn't align with codex background, but in this case, I found that this doesn't make it less enjoyable to consume.

Which begs another question - given that the Rogue Traders employ simulacra surgeons with a wealth of experience in alien biology, could they feasibly remove this diamond organ to grant Galley back his warp-presence? In xenology, it's heavily implied that the Eldar removed that organ from the Qu'orl and implanted it into the Tau to create a race more resistant to warp corruption and psychic infections such as psychnienin, so if need be they could feasibly remove it to give Galley a full soul.

That .. really sounds like something you could just make up if you wanted to. If you're going by Xenology, it certainly sounds like a logical assumption to make, at least as far as 40k storytelling usually goes. Of course, there could be unforeseen consequences with removing such an organ, beyond turning the character into a witch, but I'd say that could only add to the fun. I would certainly consider a whole bunch of Insanity Points in order, as it sounds like a surgical procedure that plays with the character's sanity.

In my mind, if a Tau parent knew their child would be faced with death upon discovery, it may make sense to sell the child to a human?

I guess this is another matter of preferred interpretation -- to me, it'd be unthinkable that the Tau would go that far as to actually kill their own just for this rather than something like exile to a frontier colony, especially given how the Ethereals consider their septs underpopulated. Then, with the Tau way of living, it would also seem difficult to actually hide a pregnancy, considering that there's very little privacy in their extended communes.

You could still modify this part of the background by having the character sold not by his original parents, but rather by a bunch of slavers the Rogue Trader came across, with Graxis being intrigued by the alien child.

Just a suggestion, mind you -- you could just as well continue as-is, rather than retconning the character's background into a kidnapping. Changing such things retroactively always feels a bit weird, but if the player didn't give much of a thought about it, I suppose he wouldn't mind .. and this way you could tie up several loose ends.

Also, thanks for not immediately going "It's not canon, it can't happen."

Hahah, years ago I might have -- but that was when I was still under the false belief that there actually is a uniform canon.

Nah, we all have our "headcanon", but as far as your game is concerned. it only matters that everyone at your table shares a common ground. It's just one of the challenges a GM has to overcome in 40k: to gauge his or her players' interpretation of the setting (usually by checking what books they were reading), and then trying to come up with a background that feels familiar to each of them.

Of course Orks have green blood! Haha

They've all transitioned over to Black Crusade now, so Insanity Points aren't really relevant anymore, but I could easily assign him a Mental Disorder instead.

As for the Tau, I'm running off of the darker-side fluff for the Tau that suggests they put convicts and captives into forced sterilization and labor camps. Hiding the pregnancy itself isn't so much the issue, more the parentage. I like your idea of slavers having sold off the child to the Rogue Trader - that's a great solution.

Not trying to whine about your idea (interesting, actually), this reminds me of playing Tales of Symphonia, and saying to myself "in a world where humans and elves don't get along well, most of the time, and half-elves are reviled by almost every elf or human person NOT named Lloyd Irving, why do so many humans and elves still create progeny? Love is one thing, but kids don't HAVE to be a result of that. They KNOW these children will be hated; they'll probably do a little bit of that hating, themselves, if you've played it, too." In the case of the Tau, I can't see an Ethereal partaking of this sort of thing, but then many people who break the rules are those very same people who fabricate those rules, so what can I say? As for making your Tau more noticeable to the warp, I think no amount of "aberrant" DNA will do it; my "soul" doesn't share me DNA, certainly not other sources of DNA. If I got a blood transfusion, and liver transplant, from a compatible friend, maybe even an arm transplant, after he has been killed, I doubt the resident psyker would begin to mistake me for him. Then again, once you've gone off into Black Crusade, I suppose some of the rules have gone out the window, by now. Best of luck with it.

For my story, I have active Tau ships in the distant Expanse, between the Rifts of Hecaton, and the Phaineal Echoes. I don't know how many Ethereals there are supposed to be. Does every ship need to have one? Several?

Well, in codex fluff, a cadre (100 Fire Warriors) is sometimes accompanied by an Ethereal, and a contingent (300-600) always has at least one. So I'd say whilst Ethereals are rare, they are not "one-per-planet" rare, and instead see them as leaders of cities and armies (albeit not on a battlefield level, leaving that to the Fire Caste commanders).

As per BFG, the lead ship in a Tau fleet may carry an Ethereal (for additional points). Farsight's expedition was known to have several Ethereals with them.

They are basically overseers, there to direct the efforts of the other castes. They don't usually micro-manage, but simply take care that the various parts of the Empire do their job according to the greater plan, often from the safety of the headquarters in the rear (although some Ethereals like Aun'va try to spread the concept of "leading from the front").

So if I were you, I'd have at least one Ethereal somewhere overseeing the activities of your Tau ships, but no more than two or three in total.

Pheromone spritzers in the life-support, on the ships?

lol

My guess with the pheromones is that its something of an imprinting process. Ethereals all emit this magic mind control aerosol, which, when "lesser" Tau come into contact with it, triggers an organ in the Tau brain that causes them to imprint on the Ethereal caste. When Ethereals mess around with mind-control brain implants and something goes sideways, said organ is crippled or weakened, allowing the Tau to regain their independence (Farsight Enclave). There's no need for continuous exposure, though there might be side benefits (sense of euphoria or whatever when exposed after imprinting, perhaps?). I'd also posit that if someone were to do some kitbash genetic splicing to create a variant pheromone and managed to expose some non-imprinted Tau, they could well usurp the place of the Ethereals. Similarly, bionic mods that affect the Tau brain might well interfere with pheromone effects, preventing Ethereals from having any special influence over the cybernetic Tau.

Alternatively, it could just be an improved version of ... charisma . At the risk of godwinning the thread, there were several real life personalities who didn't need pheromones to sway entire populaces.

Which, personally, I find has a lot more potential for Grimdark than some technological or biological imperative that can, in theory, simply be switched off.

No argument, until the Tau Fire Warriors begin to act funny, after their leaders are all gone. The "good guys with secretly less good plans" scheme the Tau are currently painted with (they gladly invite others to join them, and make a show of including them, and assimilating them, sort of like a weird cross between Ancient Rome and the Aschen, if you ever watched Stargate SG-1, but behind the doors, they are looking for your weaknesses, same as the Imperium, trying to 1984 your beliefs, sterilizing the masses of non-Tau, and always sort of treating them as second-class citizens, yada yada yada) actually support a highly charismatic leadership, swaying huge masses with their propaganda of getting out of the grimdark, and living a real, nice life, with purpose, direction, praise, and an assurance of support and safety, but the materials go and color it as some form of physical manipulation, more than just pure charisma, dogma, propaganda, and oratory.

Oh well, in the end, I won't have it matter too much. The other castes can go some time away from an Ethereal, and since they need to return to the Hidden Truth every so often, for repairs, and resupply, they'll be exposed to O'li'n Da'ya's beatific aura, or that of his underlings, regularly. I might have to decide, in my own story, if the Eldar assisting them are aware of this link, its mechanism, and if they can use it, or cause problems, for their erstwhile allies.

Farsight seems to have assassinated the Ethereals in his expedition, or at least that is heavily insinuated in the codex -- but like I said, I'm biased towards the "propaganda" interpretation (which could, however, include all sorts of subtle manipulation such as subliminal messages), as I deem that a lot darker than a flat "oh it's mind control!". The latter just feels like a cop-out, but it could just be that I've seen it used far too often in sci-fi, not to mention that it'd already be the second time this comes up as a theme for Tau (see Vespid "translator" helms).

But yeah, most of the licensed material definitely seems to point straight at various forms of remote control, be it pheromones or possibly even something psychic.

I might have to decide, in my own story, if the Eldar assisting them are aware of this link, its mechanism, and if they can use it, or cause problems, for their erstwhile allies.

I vaguely remember having read about a link there, though I can't remember whether it was a fan theory or actually something printed. :/