Darktide's easter eggs have decades of Warhammer 40,000 world-building to pull from. Fatshark's previous games, the Vermintide series, likewise had years of the Warhammer Fantasy setting's backstory to draw on, and were delightfully rich with references.
Vermintide had easter eggs from the Warhammer Fantasy novels (the vampire Franz Lohner talks about is the protagonist of Drachenfels, which also provides the setting for a DLC), the pen-and-paper RPG (expansions like Death on the Reik and Shadows Over Bögenhafen are named after its adventures), and other Warhammer videogames (Lohner has a shield with the heraldry of the Grudgebringers from Shadow of the Horned Rat and Dark Omen, and makes sly references suggesting he was actually their commander, Morgan Bernhardt).
Darktide may have slightly fewer easter eggs than the two Vermintide games at the moment, though that's only fair given that they've had years of updates and add-ons to pack them in. The easter eggs Darktide has are still plenty of fun to spot. Here's what we've found so far.
That Chaos graffiti means something
You might have been too busy escaping from prison in the prologue to notice, but servants of Chaos on Tancred Bastion took the time to leave some graffiti behind. While you're heading to the loading bay you pass containers full of junk, one of which has cryptic runes painted on the inside. They're not just random scribbles; they actually do mean something. To figure out what, we're going to have to go back a few decades.
Realm of Chaos: The Lost and the Damned, published in 1990, was one of two books that properly detailed the main Chaos gods and their followers for the first time. It was packed with info you might want for your tabletop games, like pages of runes should you need to paint a few words in the Dark Tongue (opens in new tab) on the banners waved by your miniature Chaos worshippers.
With that, we can translate some of Darktide's graffiti like the writing in that container on the Tancred Bastion. It says, in phonetic runes, "NURGLE LOVES YOU." Other cheery phrases repeated in graffiti and on flags in other maps include "KILL MAIM DESTROY," "ROT DEATH," "DEATH TO THE FALSE EMPEROR," and "FOP THE DARK GODS," which is obviously supposed to say, "FOR THE DARK GODS," but you can't blame cultists for making the occasional typo.
Not every bit of graffiti has been conveniently translated into English for us. In a few places runes spell the word "GUNAGHGHYRAN," which is the name in the Dark Tongue for Beasts of Nurgle, or "Gu'nagh'ghyran". Other runes spell out "AKSHO DHAKH" with a rune that symbolizes Nurgle between them. Thanks to commenter MadDave123 for pointing this out, that means, "Nurgle shall be called with death," according to a summoning incantation quoted in 40K second edition's Codex: Chaos. I still don't know what "BAKGURANI AGKWAMI" means, though it might be the name of someone we haven't met yet.
Other graffiti is written using the runes that refer to mutations and gifts of the gods, and those seem more randomly chosen. En route to primary control in the map Relay Station TRS-150 are runes for several of the gifts servants of Chaos can receive: tentacles, pin head, and irrational hatred. Elsewhere there are runes for rapid regeneration, cloud of flies, resilient, eye of the god, face of a beast, biting tongue, Chaos Lord, and limb loss. In the Realm of Chaos rulebooks these attributes were chosen for your characters by rolling on a random table, and seem to have been applied to the walls of Tertium Hive just as whimsically.
Some graffiti that isn't written in the Dark Tongue is an easter egg for players coming from Vermintide. It's the triangular symbol of the Horned Rat, which the skaven do seem to like scrawling on every available surface, even in games they're not in.
Our ravaged bodies are ready
The medicae servitors of Tertium Hive get some of Darktide's best lines, morosely begging to be taken with you and bemoaning their lack of purpose after their charges are used up. They're voiced by David Shaw Parker, who played innkeeper Franz Lohner in both Vermintide games as well as narrating their trailers, and he gets to utter a callback to Fatshark's previous Warhammer games when the medicare servitor asks, "Might I heal your ravaged body?"
That's a reference to witch hunter Victor Saltzpyre's immortal line, "Holy Sigmar, bless this ravaged body," which became something of a meme after its use in the original Vermintide, and was brought back for the sequel due to fan demand. I've even seen it on a T-shirt available from wish dot com of all the places.
A shout-out to Space Marine
The Graia Mk VIII Infantry Autogun's description explains that it was manufactured on the Imperial forge world of Graia, a planet that's been mentioned in Warhammer 40,000 books going back a fair way. Graia's been singled out for a nod in Darktide specifically because it's also where one of the other 40K games that did justice to the setting took place: Relic's third-person action game Space Marine was set there.
As the Graia Mk VIII's description notes, it's a weapon "in short supply after a series of calamities befell the forge world of Graia", which is certainly one way of summing up the events of Space Marine.
Not all the tattoos are of skulls
There's a plentiful selection of tattoos to choose from when designing your character, some with appropriate slogans like "DEATH BEFORE DISHONOUR." There are also a couple with a more unlikely motto, like the lower-back piece with the wreaths, which says, "THE LOVE WE SHARE."
The only time I've seen this phrase mentioned in connection with Warhammer 40,000 is in the first book in the Ciaphas Cain series, For the Emperor (opens in new tab), where it's the name of a song being sung by Amberley Vail when Cain meets her—one of several "old sentimental favourites" she sings. Guess it's still popular after all these years.
On the subject of music, Zealot Preachers will occasionally burst into song mid-mission. One of them sings the words "We all walk in His immortal shadow," which is a line from a hymn called Imperial Lobgesang. The final lines are also quoted in a cutscene from Battlefleet Gothic Armada, but here are the full lyrics, via background book The Imperial Infantryman's Uplifting Primer.
Love the Emperor,
For He is the salvation of mankind.
Obey His words,
for He will lead you into the light of the future.
Heed His wisdom,
for He will protect you from evil,
Whisper His prayers with devotion,
For they will save your soul.
Honour His servants,
For they speak in His voice.
Tremble before His majesty,
For we all walk in His immortal shadow.
I've seen that container before
Darktide really does feel like being transported down to a game of Warhammer 40,000 being played on the tabletop. The designs of all the scenery feels spot-on, from barrels to barricades, and in some cases that's because they come directly from terrain made for the miniatures game (opens in new tab).
The cargo containers are one of the most obvious pieces imported directly from Games Workshop's designs, coming from the Munitorum Armoured Containers set released as part of Battlezone Manufactorum. While all Darktide's vehicles are also based on existing 40K machines, a semi-obscure one that usually shows up connected to a trailer near those containers is a four-wheeler called a Wolfquad that's also used by Atalan Jackals (opens in new tab).
Our friends from the first trailer return
The squad of four we were introduced to in the teaser trailer (opens in new tab) didn't make it out alive, I'm afraid. You can see them strung up on a wall in the Hab Dreyko map, impaled above an arch on the way to the HL-16-11-1318 hab. Sometimes as you pass beneath them Sergeant Major Morrow will explain they were "one of our recon teams back when this started," and he'll be glad to finally learn what happened to them. You can see them meet their sticky end at the end of Darktide's intro video (opens in new tab).