Dan Abnett (or Dabnett, to his friends, of which I wish I was one) is the finest living Warhammer 40k novelist. He's written half the must read volumes in our list of the best Warhammer 40k books and, in all likelihood, will pen future additions to that list too. But, thanks to him writing at both ends of the 40k setting's 10,000 year timeline, he's also buried some seriously tantalizing hints and links into the lore, and I both adore and resent him for it. Mostly, they're just satisfying little nuggets - but his latest, still open cliffhanger could upend Games Workshop's grimdark galaxy as we know it. And I really, really hope it does.
I've written before about how I strongly believe Warhammer 40k needs another civil war to inject meaningful change and jeopardy into its fiction. Am I glad GW is adding to the Horus Heresy books with a whole series on The Scouring? Of course, I'll devour them all. But it doesn't fix my problem with the current main storyline being stagnant, repetitive, and unengaging.
There are a few threads GW has been laying down in recent years which, if pulled, could genuinely unravel the Imperium of Man and create the juicy, politically meaningful intra-human conflict I want to see in present day Warhammer 40k. The controversial return of Lion El'Jonson is one. As the wonderful Arbitor Ian explains in the video below, the Lion and Roboute Guilliman are finally going to butt heads and ideologies, and that could spill some very delicious tea indeed.
But I want to talk about a different story landmine that Dabnett himself has buried in our path. Like the Primarchs' impending brotherly schism, it dates back to the Heresy era, concerns a supremely powerful character not seen in the 40k canon since that time, and absolutely has the potential to fundamentally and irreversibly change Games Workshop's setting.
Major spoiler warning! From here on out, there be spoilers for at least five Dan Abnett books: The End and the Death (his three part finale to the Horus Heresy Siege of Terra miniseries) and the first two books of the unfinished Bequin trilogy, 2012's Pariah and 2021's Penitent. If you don't want to learn some key reveals from the plot of those books, stop here and go read one of our lovely lore guides instead! I recommend our compendium of the primarchs, and our rundown of all the Warhammer 40k factions.
With that out of the way, let me lay my (Emperor's Tarot) cards on the table: this is about Constantin Valdor and the King in Yellow. Some background: known as the First of the Ten Thousand, Valdor was the Captain-General of the Legio Custodes - the Emperor's personal bodyguards - throughout the Horus Heresy war, the preceding Great Crusade, and the Emperor's Unification War to retake Terra before that.
Valdor went through unimaginable, literal hell during the closing stage of the Siege of Terra, trapped by Horus in a warp realm of absolute darkness and forced to fight off an infinite swarm of daemons. He survived, and helped return the mortally wounded Emperor to the Golden Throne, but was thereafter silent, brooding, and apparently sickened by grief.
There's significant evidence in The End and the Death Vol. III (2024) that Valdor's gene-bred, absolute trust in the Emperor was eroded after he slew many thousands of daemons using the Apollonian Spear, a relic weapon created by the Emperor that gives the wielder the knowledge of those it kills. Shortly after the Heresy ended, Valdor vanished from Imperial records entirely and was presumed dead.
But Abnett's superb Bequin novels, following Cognitae clone-turned-novice Inquisitor Alizebeth Bequin, offer us a different story.
In those books, the Inquisition is hunting a mysterious figure known as the King in Yellow, who's understood to have spent millennia marshalling powerful forces of his own against the Imperium, cooperating along the way with a rogue's gallery of heretic cults and possibly even Chaos Space Marine legions. If you're already drawing a link between 'yellow' and the auramite gold of Custodian armor, you're on the right track. If you've read The King in Yellow, Robert W. Chambers' original 1895 collection of weird fiction short stories, which presumably served as inspiration for Abnett's writing, you win an extra point.
During the plot of 2021's Penitent, Bequin discovers that the King has his own hidden "extimate space" outside of both the material universe and the Warp, that's strongly implied to be part of the Aeldari Webway. From his private domain, the King appears to be amassing a secret force of cloned, psychically inert humans (a.k.a. blanks, or pariahs); potent artificial warp entities called Grails; and, it's implied, genetically altered, winged Space Marines.
The book's plot makes it clear that the King's master plan - apparently a major armed assault on the material galaxy, with a huge army of psyker-proof warriors emerging suddenly in the heart of the Imperium - is very close to fruition. That's pretty spicy already, but the kicker? Penitent ends with Bequin and her Inquisitor allies learning that The King in Yellow is, almost certainly, Constantin Valdor.
So, we have an 11,000+ year old Custodes warrior, apparently severely jaded by exposure to the 'truths' of the warp, at the head of a hidden army that's very close to launching a devastating surprise attack on the galaxy. We don't know the Imperium is his target, because his true motivations are still a mystery.
But we do know he's willingly worked against the Imperium over thousands of years to get to this point. And it's fair to suspect that, even more than the resolutely atheistic Roboute Guilliman, Valdor would despise the Emperor-worshipping theocracy humanity has become since his gold-plated butt slipped off the scene ten millennia ago. All the signs point to Constantin 'King in Yellow' Valdor becoming a more insidious, and certainly more interesting, threat to the carrion Imperium than Abaddon the Despoiler, the Hive Fleets, and awakening Necron dynasties combined.
I've been let down by a succession of 'current timeline' Warhammer 40k stories that, while thrilling enough, feel shallow and ineffectual. They simply set up ever scarier existential threats from chaos and xenos evils, then knock them down without any satisfying stakes or plot development.
But I'm a hopeful soul. What if, with the advent of Warhammer 40k 11th edition later this year, we get a proper story, where the Imperium has to finally confront its own demons, rather than the Warp's? Where the all but guaranteed feud between Jonson and Guilliman splits humanity's armies in half all over again? Where the Emperor's closest living genetic relative suddenly reappears on a random planet in Segmentum Obscurus and exposes the entire 41st millennium Imperium as a weeping sore of treasonous, morally debased theo-fascism?
If anything's worth another six 3% price increases on new miniatures, that would be. I live in hope. What do you think, though? Come debate the finer points of Warhammer 40k lore, ancient and modern, with me in the free Wargamer Discord community! Don't worry, we have spoiler tags, it's safe.