Somewhere in the dark, a hundred thousand green throats are bellowing the same word at once, and it is less a word than a weather system. No plan. No retreat. Just a Warboss the size of a garden shed, a wall of scrap-metal war machines welded together by enthusiasm, and the certainty that today is a very good day for a fight. The Orks have arrived, and they have brought everyone.

Welcome back to Faction Files, prising open the lore of Warhammer 40,000 one faction at a time. No dice, no meta, no points, just who these lot are, where they came from, and why they're like that. This time: the galaxy's favourite green menace. Fancy a mob of your own? Our Orks collection is right this way.

FILE 01 // Origins: engineered for a war older than the Imperium

Here is the joke the Imperium doesn't find funny: the Orks are among the oldest and most successful species in the galaxy, and they got there by accident of design. They didn't evolve on some muddy home world. They were built.

The Old Ones — the enigmatic, near-god-like race that shaped the young galaxy — built the Orks as the Krork: a warrior species grown to fight the Necrons and their C'tan star-god masters in the War in Heaven. Here's the twist: the Old Ones lost that war and were all but wiped out, while the Necrons slept away sixty million years. Their green attack dogs carried on: a weapon that outlived its war and was never switched off.

FILE 02 // The Waaagh!: they win because they believe they will

Here's what makes the Orks properly special: the whole Orkoid species is latently psychic — not robes-and-staff, lightning-from-the-fingertips psychic, but a low, constant hum every Ork gives off without knowing it. Gather enough of them, get them excited, and that hum builds into a roar: the Waaagh!, a psychic field strong enough to warp reality.

It makes them faster, tougher and harder to kill the more of them there are, and it's why their ramshackle tech works at all. An Ork gun is a lump of pipe and rivets with no business firing; it fires because the Ork holding it is certain it will. Red ones really do go faster, because every Ork knows they do. Their science is faith with a trigger: absurd, entirely canon, and the reason the tech-priests wake up screaming.

FILE 03 // How they wage war: dakka, choppy, and lots of both

Ork strategy comes down to two sacred words: dakka (more guns, more noise) and choppy (getting stuck in with something heavy and sharp). The doctrine, such as it is, is a truth every Boy knows in his bones — the more of us there are, the more likely we win, so charge and see what happens.

Behind the muscle sits the strangest supply chain in the galaxy. Meks bolt deff dreads, killa kans, battlewagons and Stompas together from scrap and belief. Painboyz perform surgery that is 90% enthusiasm. Weirdboyz channel raw Waaagh! energy and occasionally explode. Grots and squigs do the fetching, carrying and getting eaten. It only works at war.

And you cannot simply exterminate them. Orks shed microscopic fungal spores — every fallen Ork seeds the ground, and a fresh generation grows up underground, already knowing how to fight. Cleanse a world, leave it a decade, and you'll return to a brand-new Waaagh! They are less an army than a recurring condition.

FILE 04 // Ghazghkull and the clans: the prophet of the green tide

For all their chaos, the Orks split into cultures — Kultur, if we're being proper. The black-clad Goffs love a straight brawl; the flash Bad Moons are rich (Orks pay in their own teeth, or teef, and Bad Moons grow theirs fastest); the Evil Sunz worship speed; the Deathskulls loot anything not welded down; the Blood Axes are suspiciously fond of tactics; the Snakebites keep the old ways. A personality buffet.

And then there's the name the Imperium fears above all: Ghazghkull Mag Uruk Thraka. Warlord, prophet and self-declared mouthpiece of the Ork gods Gork and Mork, he did the one thing Orks almost never manage: united them, with purpose. His Waaaghs against Armageddon are among the most catastrophic invasions the Imperium has weathered, and he is still out there, planning something bigger. He is what happens when the green tide grows a brain.

FILE 05 // Why collectors love them

Here's the hobby truth: no faction in 40k is as much fun to collect as the Orks: the army you build for a table full of character, cackling the whole way through. They are also the undisputed kings of kitbashing: the aesthetic is scrap bolted to scrap by cheerful lunatics, so there's no wrong way to build them. Spare bitz, plasticard, the odd toy wheel, all fair game. A few of the joys:

• Forgiving to paint: they're meant to look grubby and mismatched, so slapdash reads as characterful, not sloppy, and contrast paints eat green skin for breakfast.
• Your clan, your colours: Goff black, Evil Sunz red, Bad Moons yellow, Deathskulls blue — pick a Kultur and the scheme picks itself.
• Ridiculous centrepieces: Stompas, Gargants and battlewagons are among the most gleefully over-the-top models in the range.

Brand new to all this? Our beginner's guide to Warhammer 40k covers the basics, the full Orks range is ready when you are, and the wider Xenos collection is worth a nose for who else lurks out there.

Threat assessment

The Imperium has burned Ork worlds to glass and killed their Warbosses; the worlds greened over and bigger Warbosses grew from the soil. There is no negotiating with a species that treats extermination as a grand day out, nor beating an enemy that grows stronger the longer the war runs. The one mercy is that Orks rarely unite — because on the day they do, whole sectors go dark.

Final thought: the Orks are the one faction in the grimdark actually having a wonderful time. No angst, no doomed nobility, just the purest and most honest joy in all of 40k, which happens to take the form of ending you. You almost can't be cross about it.

Further reading: crunch the numbers with our Orks: Army Analysis, or get the lay of the land in the Warhammer 40k Factions Hub.