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What are the Warhammer 40k Races?

Warhammer 40k races range from anything from human to zoat, and in the entire Milky Way Galaxy of the 41st Millennium there are bound to be a LOT of races. In this article we’re just going to focus on the major races of Warhammer 40k. Note that a list of Warhammer races is different from a list of Warhammer armies, but you can find the article we wrote about them here.

Aeldari

The Aeldari are one of the most ancient Warhammer 40k races, going all the way back 60 million years ago to the Old Ones and the War in Heaven. For millions of years the Aeldari–better known as the Eldar–ruled the galaxy almost uncontested.

The race of Aeldari contains five main sub factions in the Warhammer 40k universe: the Asuryani or Craftworld Eldar, the Drukhari or Dark Eldar, the Harlequins, the Exodites, and the Ynnari. All of them are the same race, but they don’t belong to the same faction in terms of gameplay, nor are they allied with one another.

Generally speaking, the Aeldari are very similar to humans, only taller, more slender and are thought to be a very beautiful race. Their skin is pale and they have pointed ears and can live a thousand years… yes, okay, they’re space elves. That’s where the Warhammer 40k races came from: Warhammer Fantasy in space. But if we depart from that comparison for a moment we can see that there are some differences that have been written into Aeldari lore in the 30+ years of Warhammer 40k history.

From a physiological point of view, it’s not even sure if the Aeldari evolved at all, because they’re a creation of the Old Ones (as are the Orks). (A brief recap, if you haven’t read the entire story: the C’Tan and the Necrons–Necrontyr–fought a long war against a race known as the Old Ones, who were incredibly powerful. To help fight in this war, the Old Ones created the creatures who would become the Aeldari and the Orks (and other races, including *maybe* the humans??? It’s hard to say.)

The Aeldari have strong psychic and mental abilities, to the degree that their mental energy helps to fuel their technology.

But the Aeldari had a fatal flaw despite (or perhaps because of) ruling the galaxy for so long: they become hedonistic, always seeking after pleasure and more pleasure, becoming lustful gluttons and this proceeded to such a degree that there was a massive warp rift and a new Chaos God was birthed. Remember that the Warp, or Immaterium, is created by the emotions of all living things–anger, hatred and rage created Khorne the Blood God, for example. So the hedonism of the Aeldari created the great Chaos God Slaanesh, the God of Excess (or, as the Aeldari called them “She who thirsts.”)

This is where everything about the Aeldari came to a screeching halt and the massive civilization, that was millions of years old, fractured (seeing as the majority of their empire was destroyed and consumed).

So what happened to each of the Aeldari Warhammer 40k races?

Well, they’re not all different Warhammer 40k races–they’re all Aeldari–but this is where things split for them. They became the Asuryani (or Craftworld Eldar), the Drukhari (or Dark Eldar), and the Exodites.

Asuryani

The Asuryani are known as the Craftworld Eldar because they exist on Craftworlds, which are enormous spaceships. Each Craftworld is its own independent civilization with their own culture. The Craftworlds are made from Wraithbone and are a sort of living creature with analogues to blood vessels and nervous system, all run by psychic energy. That psychic energy is embedded in Spirit Stones, which contain the souls of the Craft world’s dead, and all of these make up the Infinity Circuit, which is both the heart of the Craftworld and the Asuryani’s version of the afterlife.

The Asuryani are far from the “good guys” as no Warhammer 40k races are good guys. But The Asuryani are trying to live by a different code, having learned a lesson from the unleashing of Slaanesh. They are seeking to live the Asuryani Path, which define their roles in society. The main paths in Warhammer 40k gameplay are the Path of the Warrior (which produces Aspect Warriors and Exarchs, etc.), the Path of the Seer (which produce Farseers and Warlocks and Spiritseers), and the Path of the Outcast (which is an independent Path that can lead to Asuryani becoming Corsairs or Raiders, but the mighty Craftworld of Alaaitoc chose the Path of the Outcast.

The Asuryani are notable for their extremely advanced technology which is heavily influenced by their own psychic nature and their reliance the extremely strong Wraithbone, which is stronger than adamantium, and which also will heal itself as it is a living structure. The Asuryani–or at least some of them–can create and organize matter with their minds.

One of their most incredible technologies, if it can be said to be a technology, is the Webway, which is the way that the Asuryani travel through galaxy without needing to resort to the Warp. The Webway is a sort of series of wormholes or portals–fixed points in the galaxy that the Asuryani can jump to and from.

The six most prominent Craftworlds are the Alaitoc, the Black Library, the Biel-Tan, the Iyanden, the Saim-Hann, and the Ulthwe.

Alaitoc

Alaitoc is known primarily for following the Path of the Outcast, and its armies are notable for being heavy on the Rangers (snipers) and the Pathfinders (incredible snipers).

Best Alaitoc Unit: Rangers 

Black Library of Chaos

The Black Library of Chaos, also known as the Black Library (not to be confused with the Games Workshop publishing arm by the same name), is a hidden Craftworld where knowledge about the Ruinous Powers is kept within the Webway. It is protected by Farseers and Harlequins. Harlequins are often thought of as clowns, but a better conception of them is as performing historians. They hold all of the history of the Aeldari, and use performative storytelling to convey it. (And they’re also brutal killers.)

Best Black Library Unit: Harlequin Solitaire

Biel-Tan

The most militaristic of all the Craftworlds, the Biel-Tan are devoted to the Path of the Warrior. Their armies have a heavy reliance on Aspect Warriors and have relatively few Guardians.

Best Biel-Tan Unit: Dark Reapers

Iyanden

Iyanden was once one of the biggest Craftworlds, but was devastated by a war with the Tyranids that wiped out four-fifths of the population. The Iyanden still make use of their fallen, however, through heavy use of Wraithguard and Wraithlords. (Wraithguard are not living warriors but are made of Wraithbone and contain a Spirit Stone with the soul of an Asuryani who has passed on. A Wraithlord is similar, but more on the scale of a Dreadnought.)

Best Unit: Wraithguard

Saim-Hann

The Saim-Hann were one of the first Asuryani to take the threat of the Fall of the Aeldari seriously. They are much less connected to the other Craftworlds and are prideful and suspicious, often leading to skirmishes between them and other Craftworlds. The Saim-Hann are best known in battle for their vehicles.

Best Unit: Jet Bikes

Ulthwe

Orbiting the Eye of Terror, Ulthwe is on constant threat of war with the daemons of Chaos. This has led their militia, which would normally be Guardians on other Craftworld, to be called the Black Guardians and be an altogether better fighting force.

Best Unit: Black Guardians

Drukhari

The Drukhari, also known as the Dark Eldar, are a vile and pernicious race–everything debauched that the Aeldari once were that gave rise to Slaanesh, only much more so. The Drukhari thrive on piracy which leads to taking slaves who they will torture for their own pleasure. But it is for more than their pleasure, but for “the Thirst”, which is their maddening desire for other beings’ souls.

The Drukhari do not live on multiple worlds like the humans, or multiple Craftworlds like the Asuryani, but reside solely in one massive city–the City of Commorragh–that exists within the Webway. They are able to make their lightning raids so quickly and fiercely by popping in and out of the Webway to enslave their unsuspecting targets.

Just as intelligent and technologically advanced as their Asuryani brethren, the Drukhari use that intelligence toward the most depraved and diabolical ends. It is said that a psyker who can see the soul or aura of others will only see blackness when looking at a Drukhari. However, despite having the same psychic abilities that their Asuryani relatives do, the Drukhari do not use it as they don’t wish to draw the attention of Slaanesh.

Their weapons in war are so technologically advanced as to appear to be magic to the uninitiated, but they still delight in the type of fighting that will draw the most pain: using instruments designs to burn, sting, and flay. Think acid-tipped whips and needles.

In war, the Drukhari are ever the raiders, hitting fast and hard. They’re a fragile race, and their armor is not as powerful as many other Warhammer 40k races, so they are not the type for prolonged conflicts or sieges.

The Drukhari do not have any true leader that unites them as a whole, but they exist as an amalgamation of Kabals and Wych Cults. They are held together by common cause, but that doesn’t mean the various Kabals and Cults will work with each other.

While it can be said that there are no true “good guys” in the 41st Millennium, of all the Warhammer 40k races, the Drukhari are definitely “bad guys.”

Best Unit: Succubus

The Exodites

The Exodites are Aeldari who left before the great Fall of the Aeldari, able to see that their civilization was coming apart because of hedonism. The Exodites live in far flung worlds and have much simpler, less technological lives than the Asuryani or Drukhari. They have turned their back on the old ways and have turned to a more primitive way of living–working the land and laboring with their hands.

The Exodites have many worlds they call home, but they are nomadic and may only stay for a few months at a time at each one. They follow herds and follow seasons. Many of the Exodite worlds are homes to Megadons or other dinosaur-like reptiles which the Exodites call dragons. Those who have tamed the beasts are known as Dragon Knights.

One fragment of old technology that the Exodites retain is something akin to the Asuryani Infinity Circuit, only the Exodites call it the World Spirit. This is a psychic matrix where their souls are stored when they die.

The Exodites are almost never seen on the tabletop in battle, but whenever there is talk of the introduction of new Warhammer 40k races, the Exodites are often brought up.

Necrons, the C’Tan and the Old Ones

It is impossible to tell the story of the C’Tan without telling the story of the Necrons or Necrontyr, as they are inextricably woven together. And their story can’t be told without explaining the Old Ones.

The C’Tan are thought to be the oldest intelligent beings in the galaxy, though no one can be sure, as they are so ancient. it is said that the C’Tan were created at the beginning of the universe. They are called Star Gods and came aware before the first planets had cooled.

Physically, there isn’t much to a C’Tan–they are beings of gas and energy that dwell next to stars and absorb the light and radiation that the stars emit. It wasn’t until they came into contact with the Necrontyr that they were able to take a more physical form, using the living metal necrodermis.

The Necronytr were an ancient race (some sixty-odd million years ago) who were not too different from humans, but who led terribly brief, sickly lives. They were excruciatingly pained by the sun of their homeworld, and they sought nothing but cures for how to extend their life. As they took to the stars eventually, they developed stasis crypts and the necrodermis as ways to keep themselves alive while they traveled slowly through the galaxy. They spread to create an empire, but were always weak and feeble, and always looking for a way to live longer.

During their expansion, the Necrontyr came into contact with an ancient race known as the Old Ones, who were far more powerful, and who had solved the problem of immortality. When the Old Ones refused to share this knowledge with the Necrontyr, the Necrontyr went to war.

The Old Ones were beating the Necrontyr pretty soundly, until the Necrontyr came into contact with the C’Tan. This was an accidental meeting, but both thought they could make use of the other. The Necrontyr wanted the C’Tan’s sheer power, and the C’Tan wanted the Necrontyrs’ corporeal forms. In a series of betrayals and tricks that can be read in full here (The War In Heaven) the C’Tan tricked the Necrontyr into giving them the Necrodermis, which gave them physical form, after which they enslaved the Necrontyr and together they defeated the Old Ones.

However, there was time for one more betrayal, and The Silent King of the Necrontyr, whose peoples’ souls had been sucked out of them and permanently trapped in metal robot bodies, went to war against the weary C’Tan and destroyed them–or, fragmented them.

Now the Necrons exist as an undead robot race that is powerful for its ability to raise their warriors from death, but also powerful because they control shards of the C’Tan which they use as powerful weapons. In fact, many of the most powerful weapons in all of Warhammer 40k belong to the Necrons.

Best Unit of the C’Tan: the Nightbringer

Best Unit of the Necrons: the Necron Warriors

Chaos Daemon

I suppose this is a race, if Chaos Daemons can even be termed a race or have a species. But they are a major force in the game and therefore the Chaos Daemons deserve a place in the great Warhammer 40k races. Chaos daemons are intelligent beings made from pure psychic energy, and they are the embodiment of the Chaos Gods (and Chaos generally).

Daemons are created by the four Chaos Gods but exist as substance of the Immaterium. The daemon will tend to bear the appearance of the God that it represents. They do not truly have a physical form but they project a form of emotion and psychic energy. Consequently, a daemon is never really killed, but it gets sent back to the Warp where it essentially returns to its psychic state. (It is said that killed daemons are ridiculed by their fellow daemons and seek to avenge themselves.)

Daemons do not have a will of their own, but do the bidding of their masters.

There are several types of daemons:

Greater Daemons

Greater daemons are nearly as powerful as the Chaos God who they represent, and can occasionally be conduits for that God to insert his presence. They have power over all the lesser daemons both in the Immaterium and Materium. The Greater Daemons are: the Bloodthirster (Khorne), the Lord of Change (Tzeentch), the Keeper of Secrets (Slaanesh), and the Great Unclean One (Nurgle).

Daemon Princes

A Daemon Prince is a mortal who has gained such favor in the sight of the god to whom he is dedicated that the god elevates the mortal to the role of daemon prince. Although this can happen to any Chaos Champion, the most well-known daemon princes are the traitor Primarchs who have fallen to Chaos. This includes Magnus the Red and Mortarion. It is known that Angron has been elevated to a daemon prince by Khorne, and it’s anticipated that we may see a release soon of Angron as a model.

Lesser Daemons

Lesser daemons make up the bulk of Chaos armies, and can include Khorne’s Bloodletters, Nurgle’s Poxwalkers, Slaanesh’s Daemonettes, and Tzeentch’s Flamers of Tzeentch (and many more.)

There are also Daemonic Creatures, Daemonic Beasts, and Daemonic Steeds.

There are also unaligned daemons who exist in the Immaterium but do not hold allegiance to any particular Chaos God. These are often in the camp of Chaos Undivided, but can also take the form of Astral Spectres (which are essentially ghosts that make use of the Immaterium) as well as Warp Predators which are dangerous being that exist in the Warp that obey no one.

Best Unit of the Greater Daemons: Lord of Change

Best Unit of the Daemon Princes: Mortarion

Best Unit of the Lower Daemons: Poxwalkers

Genestealer Cult

Genestealer Cults are a different Warhammer 40k race, though they once were human. The basic premise of the Genestealer Cults is that the genestealers sneak onto a world, get down in the belly of a hive world or a mine, and then begin to infect the population with its own genes, creating both beings that are not quite human and not quite Genestealer, but who worship and revere the Genestealers as some sort of holy beings or messiahs.

The cultists take different forms and it’s hard to say where human ends and genestealer begins, as the lines are blurred. The cultists will live like this for generation after generation, evolving more and more, becoming less and less human with every birth.

And, when the Genestealer Cult is powerful enough, they will rise up to take over their world, desperate to get a signal to the Tyranid Hive Fleets that they have made the world ready for the Hive Fleet to consume it.

The order of the generations goes like this: it begins with a pure Genestealer, known as Purii, who will insert his genes into a living host. The host, known as Conagii, go back to their society–seemingly normal–and finds a mate and begins to have children. The only physical difference between a normal human and a Contagii is that the Contagii may have a slightly different hue to their skin.

The child of the Contagii, or Generation One, the Maelignaci, is a hybrid who looks much like a genestealer, often with multiple limbs. In the game these are known as the Acolyte Hybrids.

Generation Two, the Hybrids, look more human than the Acolyte Hybrids, but have discolored skin and features that are clearly alien. They also may have more than two arms, but are more human.

Generation Three, the True Hybrid, can be mistaken for a human, albeit an abhuman. But in the deep delves of a hive world, people are used to mutants. They are most readily recognized by the ridges in their foreheads and the color of their skin.

Generation Four can pass as a completely normal human, and it is this generation that begins to worm their way into positions of power. Previous generations are merely the workers and the warriors–it is the Fourth Generation who will devise the plans whereby the Tyranid Fleet can be hailed. These are known as Primacii, and in the game they are the Neophyte Hybrids. These Hybrids will join the Planetary Defense Force or the Astra Militarum to gain access to weapons.

Finally, at the fifth generation, more Purii–true Genestealers–are created.

Best Unit of the Genestealers: Atalan Jackals

Human

Much can be said about the humans as a Warhammer 40k race, and they are as varied as the Xenos. The Imperium of Man is said to rule over millions of worlds with millions of people on each, and consequently there is a wide variety of humans and cultures. For an in depth discussion of the most notable variants of the Imperial Guard (or Astra Militarum) read this article here.

But the humans are not merely the citizens of planets, the Planetary Defense Forces, and the Imperial Guard. Humans also lead every part of the Imperium of Man, including the Space Marines, the Sisters of Battle, the Inquisitors, the Adeptus Mechanicus (to some degree), the Adeptus Custodes, the Sisters of Silence, and more.

Best Unit of the Imperial Guard: Cadian Shock Troops

Some of these factions of humans are not merely humans but true super humans. The first in that category are the Space Marines.

Space Marines

Space Marines are genetically and psychologically enhanced super humans who bear the gene-seed of their Primarch, the leader of their Legion. The Primarchs, in turn, are said to bear the genes of the Emperor of Mankind himself. And the Emperor, as we all know, is some kind of immortal super-psychic badass.

Space Marines begin their lives as regular humans, very often on harsh worlds in terrible conditions. Each chapter of the Space Marines has their own methods of recruiting, but generally the recruits are tough fighters, from gangs or tribes that hunt and kill–Hive Worlds and Death Worlds make some of the best recruiting fields. But being recruited is only the beginning because then the candidate has to survive test after test and fight after fight to qualify before they ever get to their genetic modification.

The gene-seed that is implanted in the Space Marines carries all of the genetic information of their Primarch, but that includes its flaws as well: the Blood Angels suffer from the Black Rage and the Red Thirst because of their gene-seed, and the Space Wolves have the Mark of the Wulfen.

Nineteen organs were implanted in Space Marines for Millennia, but the Primaris Space Marines add three more organs. Overall, these twenty two organs enhance a Marine’s physical and mental prowess, with the most important being the gene-seed, and the second most important being the Black Carapace, the under-skin armor around the ribcage of the neophyte. It is through this Black Carapace that the Space Marine is able to interact with his power armor, connecting to the Machine Spirit.

After all the implantation, there is intensive physical and mental conditioning where the Space Marine is trained on how to use his new body. (The process of becoming a Space Marine makes the Neophyte’s body unrecognizable even to himself as he grows so much both in muscle and bone mass but also in height and shape.)

In the lore, Space Marines are considered the most elite of all troops, near gods among mortals. They are pictured as mighty saviors or cold killers. They are efficient, powerful, and are literally incapable of feeling fear. In game play, they’re still powerful, but understandably more balanced with other Warhammer 40k races.

Best Unit of the Space Marines: Incursors

Abhuman

While not different races, Abhumans are “abnormal humans” or “aberrant humans” that differ from humans in really meaningful and important ways. Sometimes this abnormality is caused by some kind of radiation or mutation, but sometimes–as in the case of the Squats–it was caused by the nature of the world they inhabited.

Some of the best known Abhumans are:

Beastmen

Beastmen are not seen in current editions of Warhammer 40k, but were very much a part of old Imperial Guard lists from the first edition, back when Warhammer 40k was much more of a transfer of Warhammer Fantasy into science fiction. Beastmen are men with horns and hoofs, like goat men or satyrs. They haven’t been in the game for decades.

Squats

The Squats were a society of what were essentially Space Dwarves. Very blue-collar tough-guys, the Squats were miners and rode three-wheeled motorcycles. Squats were a fan favorite and continue to be, but were discontinued because Games Workshop felt that this Warhammer 40k race was too silly or irreverent to be part of their grimdark world. However, there are rumors that the Squats may be making a comeback in 2022. (There have been a few models released for Necromunda in the past few years.) Read a full article about the Squats here.

NOTE: SEE THE LEAGUES OF VOTANN MENTION BELOW

Ogryns

Ogryns are one Warhammer Fantasy translation that managed to stay. As the name suggests, these are Ogres, and are portrayed very much as traditional ogres: big, tough and stupid. Used by the Imperial Guard as shock troops, they are one of the few Imperial Guard troops that are actually good in close combat.

Best Unit: Bullgryns

Ratlings

These are the Warhammer 40k race equivalent of Warhammer Fantasy halflings. But, in the 41st Millennium, they are portrayed as sneaky snipers and scouts. They still exist in the current Imperial Guard lists, but are seldom used.

Best Unit: Ratlings

Navigators

Although Navigators never appear on the tabletop, they’re worth mentioning while discussing Abhumans. Navigators are those who must guide their ships through the Warp, and as has been mentioned, the Warp is a mentally taxing place that can drive a regular person–or even a Space Marine–insane. Navigators are mutants that have a Navigator Gene giving them a third eye, the Warp Eye, and they use psychic senses to navigate through the Warp. (Navigators’ existence and similarity to the Navigators in Dune has been mentioned as one of many places where Warhammer 40k borrows from great science fiction works.)

Leagues of Votann

Leagues of Votann are, or were, Squats, but refer to themselves as Kin. The Leagues of Votann are an advanced race that are driven by mercantilism and profit. They are squat little dwarven-looking folk, like the Squats, but they are their own distinct culture and very different from the Squats that we see in Necromunda.

Essentially, the Kin have been on some resource-rich planets in the center of the universe but cut off from most of the Imperium–until recently. They were once humans who settled these wars before the Time of Strife and grew different in appearance over the 30-odd thousand years of living in harsh conditions.

One notable thing about the Leagues of Votann is that they not only allow for the existence of artificial intelligence (which the Imperium sees as the worst heresy) but they see the artificially intelligent robots as equals and serve side by side, in business and in war.

So what are “leagues” and what are “Votann”? The leagues were originally military organizations that grew up around protecting the Votann, but have since grown into a kind of ancient clan and society–the Leagues of Votann are indeed separate leagues that operate together from time to time. The Votann are mysterious ancient machine intelligences which are viewed as sacred. There was a time when the Votann would be the all-ruling, all-knowing demi-gods, but now many of them are so dusty and hidden that they may not even function. One of them is rumored to be mad. And the Kin definitely do not talk about the Votann to anyone outside of themselves, or do anything that would risk the loss of one.

Known for their technology, and somewhat technowizardy, the Leagues of Votann have powered armor, Land Fortress vehicles, and large weapons.

Best Unit: Brokhyr Thunderkyn

Orks

Orks are, unsurprisingly, the Warhammer 40k races version of the Warhammer Fantasy Orks, which are versions of JRR Tolkien’s Orcs. In Warhammer 40k (and in Warhammer Fantasy, to a lesser extent) the Orks are almost played as the comic relief. They are green-skinned and brutal, but also gleeful and chummy. They speak with heavy Cockney accents, will wear bright and outlandish costumes like pirate hats, have a truly hilarious technology.

The Orks, for starters, are not mammals or reptiles but actually fungus. They don’t feel pain–or at least they feel very little pain–and can survive even the most ridiculous of surgeries, like replacing both feet with a wheel, or placing a head on a robot body.

The power of the WAAAGH is a psychological or possibly psychic effect that basically means that if enough Orks believe in something, it will actually happen. This is effectively how all Ork machinery, including cybernetics and weapons, work. The Adeptus Mechanicus has tried and failed to reverse engineer Ork technology, finding that it is quite impossible to actually do anything–and yet it does because of the WAAAGH. (The Adeptus Mechanicus chalks this up to a Machine Spirit that belongs to the Orks.)

Orks live by one simple rule: whoever is the strongest is in charge. Warbosses become warbosses through killing other warbosses. The biggest and baddest of them all, Ghazghkhull Thraka, has defeated hundreds of other Orks. The Orks worship two gods: Gork and Mork. One is “brutal but cunning” and the other is “cunning but brutal”.

There are subclasses of Warhammer 40k races within the Orks: the Gretchin (or “Grots”) and the Snotlings, which are listed from large to small. The Gretchins are shorter than Orks but can still fulfill some battlefield roles. The snotlings are smaller still and when they aren’t finding a sword to polish will put to some other purpose, like being as food or ammunition.

And as long as we’re talking about Warhammer 40k races, there should be mention of Squigs, which are also a transplant from Warhammer Fantasy but which (seemingly) have no equivalent in general fantasy lore. A squig is essentially a big ball, about three-quarters the height of an Ork (though they can get much bigger) with an enormous mouth, a tail, and two legs. Squigs are used alternately as weapons, transportation, garbage receptacles, and pets.

Best Ork Unit: Boyz

Slann

Little is known about the Slann, but they deserve a mention as a notable Warhammer 40k race. They Slann are ancient, and are also a port from Warhammer Fantasy (that, there, are related to the Lizardmen or Seraphon). The Slann are some of the oldest beings in the Warhammer 40k universe. They are said to have counseled the Aeldari millions of years before the Fall of the Aeldari about the dangers of the Warp.

At one point the Slann spanned much of the galaxy, but their civilization began to dim, not through violent conflict but perhaps due to their philosophizing on their nature as immortals. Slann still exist, but not as a cohesive unit, and they have lost nearly all of their technology. They can be found on the occasional world in small bands and tribes, with cultures that, in game (as with the Seraphon) are aesthetically similar to Mesoamerica.

There is some question in the Warhammer 40k canon as to whether or not the Slann ARE the Old Ones, or whether they are merely contemporaries with them. Both have been stated at different times.

T’au

In the Warhammer 40k world where everyone is bad, perhaps the most good (or at least the best of the bad) is the T’au. This isn’t to say that the T’au aren’t constantly at war (because “there is only war”) but the T’au are the only known Warhammer 40k race that does things for the “greater good.” Some have used this to refer to the T’au as Space Communists, and if you like that label you can use it, but what it basically means is that the T’au are seeking peace and they will do whatever it takes (up to and including genocide) to achieve peace.

What this means, however, is that the T’au are one of the only Warhammer 40k races that will not automatically exterminate the populations they beat in battle. Instead, the T’au are not simply the T’au but the T’au Empire, consisting of many different races.

The T’au themselves are humanoid, blue, and fragile. They have hoofed feet and hands with three fingers and a thumb. They are separated into a caste system that is designed to place the good of the many over the good of the individual: the castes are the Fire Caste (most of the military), Earth Caste (workers, artists, and scientists), Water Caste (merchants and diplomats), Air Caste (the T’au Navy), and the Ethereals, who are the religious and political leaders.

The T’au, because of their fragility, utilize high technology in war, and make use of warsuits armed with truly awesome firepower. The guns that the warsuits use, including the Rail Gun and the Pulse Blastcannon, are incredibly devastating, able to kill an Imperial Knight in a single shot. That said, even in warsuits the T’au are very weak in close combat. In a T’au army, close combat is almost universally handled by some of the T’au Empire allies, the Kroot.

Best T’au Unit: KV128 Stormsurge

Kroot

The Kroot are a semi-birdlike Warhammer 40k race that are members of the T’au Empire. They are nearly half again as tall as a human, with a beak and with pointy quills sticking out of the back of their heads. However, not all Kroot look the same, and this is because Kroot can actually change their genetics by what they eat–including the enemies who they eat on the battlefield. Kroot leaders are known as Shapers because their goal is to shape their followers into whatever traits they need–if they need to be stronger, they will fight and eat the Orks. If they need to be able to fly, they will fight and eat flyers.

Coming from the homeworld of Pech, a forested, jungle planet, the Kroot appear to be nearly feral, but are actually relatively sophisticated. While their technology is limited and relies a great deal on equipment that they get from the T’au, they are still a formidable opponent in a fight. Primarily using a rifle that is similar to the T’au Pulse Rifle, the Kroot Rifle also has a barb or blade on the end of it that can be used in close combat. Their largest gun is mounted on the back of a Krootox, a beast from Pech.

Kroot are forbidden from eating Tyranids, humans who worship chaos, and the T’au.

Best Kroot Unit: Kroot Shaper

Tyranids

Tyranids have no Warhammer Fantasy equivalent, and are probably most inspired from the “buggers” from Starship Troopers. Large, insectoid creatures that can be as big as a man or as large as an entire fleet of ships, the Tyranids have one goal and one goal alone–to increase their bio-mass. They eat to gain more bio-mass and will continue eating and eating until either there is nothing left to eat or until they deem that they are losing more bio-mass in the conflict than they are gaining, in which case they’ll retreat.

Traveling in massive Hive Ships, the Tyranids are known by their hives. It is known that the Tyranids, unlike all the other Warhammer 40k races, are from outside the Milky Way Galaxy. The first known sighting of Tyranids by the Imperium was when Hive Fleet Behemoth began invading Imperium space, devouring world after world until they were beaten back by the Ultramarines at the Battle of Macragge. However, there is evidence that Tyranids were in Imperium space at least 7000 years prior, as some were found buried in the ice by Commissar Ciaphas Cain.

Tyranids operate with a Hive Mind, which means that they all are connected and really have little to no willpower or consciousness of their own. They act as a whole, and the Hive Mind spans not just battlefields but across hundreds of light years. There is some communication on the battlefield, through a form of telepathy that is controlled by “synapse” creatures, which include Tyranid Warriors and Hive Tyrants. If these links are broken the Tyranids will still attack and follow the greater hive mind, but will react more on instinctive urges to attack and defend and may not use the strategy employed by the synapse creatures.

The Tyranids, unlike all other Warhammer 40k races, do not use the Warp or Webway as a method of faster-than-light travel. Instead, they can travel faster-than-light using a bio-ship called a Narvhal. This can’t be used near large stars or planets, however, so a Tyranid hive must leave a star system using slower-than-light travel before they can use the Narvhal to jump to another star.

The scariest part of the Tyranids’ presence is the thought that the current Hives of Tyranids–that are nigh unstoppable–may not be a full force of Tyranids but are merely a scouting party for a much larger force of Tyranids that is still in the void of space.

Best Tyranid Unit: Hive Guard

Zoats

The last of the Warhammer 40k races we’ll mention here are the Zoats, which appeared in the very early version of Rogue Trader, disappeared for decades, and then–like the Squats–have peeked out of the corners as though we may see them come back.

Zoats are essentially reptilian centaurs, with four legs and two arm. They were originally used as Tyranid diplomats, as they can speak and use logic. But they are not actually Tyranid in origin, but merely enslaved (or perhaps bioconstructed) beings of a different race entirely.

Zoats made their reemergence in an expansion of Blackstone Fortress. It is rumored that they may be a race that could be expanded into a full army.