The 3rd Edition Necron Codex slipped a sentence into a single paragraph that quietly broke part of 40K’s universe. It said that in the dying years of the War in Heaven, the Old Ones created two more warrior species to defend their last strongholds. One was the Jokaero. The other was the Krork.
The Krork are the ancestors of the Orks. The Old Ones (the cold-blooded reptilian engineers who built the Aeldari, designed the Webway, and seeded humanity’s primate ancestors on primordial Terra) built the Orks too. Or rather, they built something the Orks remember as the Brainboyz, and the Brainboyz built the Orks. That’s the story the Orks tell themselves. They have it more right than they should. The Brainboyz baked it into them at the cellular level.
What the Brainboyz actually were
The Old Ones had a problem. They had spent millions of years uplifting younger species, weaving the Webway, and basically running the galaxy as a slow, gentle hothouse for new intelligent life. Then the Necrontyr (bitter, short-lived, jealous) found the C’tan, traded their souls for living-metal bodies, and started the second phase of the War in Heaven with a fresh army of immortal soulless killing machines. The Necrons.
The Old Ones lost. Or at least they lost the ability to keep doing things their gentle way. The C’tan-led Necron empire was burning the galaxy, and the Old Ones built warrior species in response.
The Aeldari came first. Then a few species that mostly faded from later lore — the Rashan, the K’nib. Then, when even that wasn’t enough and the Enslavers were starting to spill in through the cracks the Necrons had ripped in reality, the Old Ones built the Krork. Big enough to wear power armour casually. Hardy enough to laugh off the kind of weaponry the Necrons specialised in. Psychically wired into the Warp in a way that meant a horde of them got measurably smarter and stronger the more of them stood in one place.
That gestalt psychic field is the design choice that matters. The Old Ones built a swarm with collective psychic feedback baked in. The swarm gets smarter the more dense it is. That’s the central design feature.
The Brainboyz are the Orks’ name for the Old Ones, or for some specific caste of them, or for a smaller engineered species the Old Ones used as bio-architects. The lore is genuinely fuzzy on which. I’ve read the codex passage maybe ten times across editions and I’m still not sure GW knows. What’s clear is that the Brainboyz baked information directly into Ork DNA. It sits at the cellular level. Every Mekboy is born already understanding internal combustion, gravity, voltage, and how to bolt a turret to a flatbed without it falling off in motion. Painboyz are born with rough surgical instincts. Weirdboyz are born wired into the gestalt field.
If you’ve read the Orks 101 piece the broad strokes will be familiar. The Brainboyz are the bit that explains why those broad strokes hold up.
The Krork were bigger
The next part is the bit that doesn’t get talked about much.
The lore explicitly puts the Krork as the ancestors of modern Orks, with the implication that what we see on the tabletop now is a regressed form. Bigger physically. Smarter individually, less reliant on the gestalt to function on their own. Better-equipped. They fought in the War in Heaven alongside the Aeldari, against C’tan-backed Necron armies, and they were apparently good at it. The Aeldari beat them after the Old Ones disappeared, but it was close.
What we play with on the tabletop in 41st-millennium 40K is a degraded weapon. The Brainboyz left, the gestalt knowledge stayed in the genes, and over sixty million years the species drifted away from being a precision tool. The genetic instructions stayed put. Everything else changed.
The cellular knowledge is degraded too. A modern Mekboy builds Battlewagons. The Krork fielded gravitic weapons that genuinely scared the Necrons. Sixty million years sit between the two.
I want to be careful here. The lore on this is rumoured more than confirmed, and GW has rolled back some of the harder claims about Krork advancement over the last couple of editions. There’s a version of all this where the “Krork were bigger and better” stuff is a misreading of a single throwaway line. I lean toward believing it because it makes the rest of Ork lore make more sense, but the source for it is rumour-tier in places.
Mekboyz, Painboyz, and the genetics that won’t shut up
The Brainboyz angle is the only one I’ve seen that fully explains why Orkoid technology works.
The standard joke is that Mek tech functions because Orks believe it functions, and there’s a real strand of lore that supports that: Ork psychic gestalt belief warps reality enough to make a red Trukk go faster. Underneath that is a deeper layer. The Mek isn’t pulling design ideas out of nowhere. He has a partial, corrupted, multi-million-year-old engineering manual encoded in his cells. He doesn’t know he’s reading it. He just looks at scrap metal and “knows” what to do with it. The fact that what he knows is half-remembered Old Ones tech, filtered through sixty million years of degradation and a brain that mostly wants to hit things, is why Mek wagons look the way they look.
Painboyz are the same trick in a more disturbing register. They’re working from a corrupted Old Ones bio-engineering manual. That’s why they can perform field surgery that no civilised xenos species would survive, and that’s also why an Ork who “shouldn’t” be alive (head shot off, half a torso missing, one lung) keeps getting back up. The Brainboyz built bioweapons, and the Painboy is what keeps them running on the battlefield.
Weirdboyz are the worst version. Psychic antennae for the gestalt, hardwired in. A weapons system that gets stronger when more units join the battle is a weapons system you build deliberately. I wrote about the new Weirdboy when his model dropped, and the longer I sit with the kit, the more I think GW was leaning into this exact angle. The Weirdboy’s wired into that gestalt directly.
It’s the same engineering lineage as the Jokaero, the other species the Old Ones built in the desperate phase of the War in Heaven.
Where I actually got pulled into this
I bought the first three books of The Beast Arises off a Black Library half-price sale in 2018, mostly because I wanted Imperial Fists pain and the cover art looked good. I didn’t expect to finish the series. I finished the series. Twelve books, read in sequence, mostly on commutes. Kiran kept asking when I was going to be done so we could resume our Kill Team campaign and I kept telling him “after the next one.” That campaign sat untouched for five months while I read about Ork attack moons.
The series is the closest 40K has ever come to writing the Krork hypothesis as canon. The Orks of WAAAGH! The Beast were taller, smarter, and more organised than anything the Imperium had records of. The Beast himself spoke fluent Gothic and ran a city. The Imperium calls them “Beast” Orks like it’s a separate sub-species, and structurally that’s what they are. Something in the Ork genome had partially woken up. It had been dormant for sixty million years.
The Beast and what it might mean
The War of the Beast (M32, roughly 544 to 546) is the second-largest war the Imperium has ever fought, after the Heresy. It nearly wiped out the Imperial Fists at Ardamantua, killed billions of citizens, killed several Chapter Masters, and ended with Vulkan apparently dying inside a temple-Gargant. The Imperium created the Deathwatch and the Ordo Xenos as a direct response.
What’s missing from most write-ups of the war is the genetic angle. The Beast’s Orks were Orks where the Krork heritage had partially expressed. Bigger. Smarter. Capable of assembling teleport networks and gravitic weapons that scared the Mechanicus enough to start illegal experiments. The Beast itself was ten metres tall, mega-armoured, fluent in Gothic, and the Imperium’s strategos couldn’t make sense of how it could exist.
The Brainboyz framing is the only framing that does. The Krork instructions in the Ork genome are still there, just dormant. Under the right pressure (a sufficient gestalt density, a Warboss with the right psychic profile, an Attack Moon already in orbit when the seed Orks landed) the species starts walking back toward what it was originally built to be. The Beast was a partial Krork awakening. So, arguably, is Ghazghkull, in the way his presence makes nearby Orks bigger and more coherent.
The current Armageddon book has Ghazghkull explicitly saying things about the Orks getting “bigger” that the lore-conscious reader is going to read with a very specific subtext. The Brainboyz lore is still in place, which means GW can pull a Krork-resurgence storyline at any point.
So how do you sit with this as a player
Okay so look. Orks are funny. They are. They will always be funny. The trukks named MORK SMASH, the squigs that bite the wrong character, the dakkajets that fall apart on the table, the Mek who fixes a gun by hitting it with a wrench.
The army’s whole existence runs on a sixty-million-year-old engineering project that the engineers walked away from before finishing. Imagine inheriting a house from someone you never met, except the house keeps trying to bite you. Every Squig is broken inheritance. Every Mek is reading a manual that’s been corrupted past legibility. The Weirdboys are still antennae for a signal whose source went extinct sixty million years ago. The Orks don’t know any of this. They’ve never been told.
This is the thing the army doesn’t really get credit for. The Boyz on the table don’t know any of it. They never will, because the engineers who designed them haven’t been around for sixty million years.
