Just I said somewhere - I'm a layman. By a long time I read translated things, mostly Warhammer Fantasy. I shortly lost interest with annulation of WF and return with Total War. Getting into 40k is a recent thing for me, when I discovered Unification Mod to Soulstorm.
Ah, that explains it. Dawn of War takes place around the 4th Edition era; the Vespid and chunky Stealth Suits (
who used to look like slightly bulkier Fire Warriors) used by the Tau (who are now called the T'au because they didn't let GW copyright a letter) were introduced in that era. In this time the Necrons still were a bunch of implacable Terminators (not those guys) who lacked all personality, before 5th Edition rolled around and they were turned into a bunch of space Egyptians with characters like the guy who can sorta see the future but sneakily sets up things so that the outcome is as he predicts, the massive kleptomaniac who steals entire regiments of Imperial Guardsmen for his collection and feuds with the previous guy, and the guy with space Egyptian Alzheimer's who needs his bodyguard to clean up after him and keep the royal court in check.
Well, that sucks. There is anything good in new fluff?
Up to 7th edition there were some minor lore changes here and there to keep things trudging along, a few name changes like Astra Militarum being the new name for the Imperial Guard (again for copyright reasons). Over the course of the editions up to 9th (the previous as of a few weeks) several new armies popped up: the Adeptus Mechanicus got their own army now, there's the mini-titans of the Imperial Knights and their Chaos equivalents, the Harlequins got their own proper Codex again, the Genestealer Cults got their own Codex to serve as the vanguard to a proper Tyranid force, the Adeptus Custodes get their own book and are joined by the Sisters of Silence, and the forces of Chaos got split off into several books of their own: the Thousand Sons, Death Guard and World Eaters have their own Codexes now, while the Emperor's Children can, for lack of a better term, get fucked. You can still field most of the god-aligned unit in the base Chaos Codex, but the true specialists are in their own book. Oh, and the Leagues of Votann, who are space dwarfs but definitely not Squats. They were released and promptly forgotten about.
Then 8th edition hit with the biggest lore changes so far. On top of major rule changes to the point where every army got a reworked mini-Codex when the edition hit, there was the teeny little issue of Cadia getting blown the fuck up. Abaddon's Black Crusade finally worked and he managed to fuck Cadia up so bad that it tore the galaxy in half:
This created the Dark Imperium, to the galactic north-east of the Great Rift that now barely able to navigate using the light of the Astronomican. The Great Rift is essentually the Eye of Terror massively elongated and nothing can pass through without being ripped apart by the Warp. There's only two corridors that can be "safely" navigated: one close to the Eye of Terror and one north to Ultramar and the Tau Empire (look for purple text). Things are pretty bleak, but then this nerd called Belisarius Cawl burst out of his basement after locking himself there for 10000 years and presenting the Primaris Project: he spent ten millenia pouring over the Space Marine design and created the Primaris Marines, essentially Space Marines 2. They were handed out across all the Marine chapters they could find, with some of them (the Flesh Tearers, some of the Black Templars) not being all too happy with them. They've got all sorts of new models with new weapons and gear, with older models being slowly phased out (RIP old Dreadnought).
And who better to spread the good word than none other than pappa Smurf himself, Roboute Guilliman. That's right, through a mix of Cawl being a massive nerd and some Eldar woman kissing his booboo (read: gaping neck wound caused by his daemonic brother Fulgrim) away Big Bobby G woke up and started to help the Imperium back up after complaining about why they didn't let him die and wake him up to this hellscape of an Imperium. He's trying his best and had to dispose the High Lords of Terra when they objected to being ousted, but he's doing well. He lauched the Indomitus Crusade to get the Imperium back together, and it's working out so well there's an unprescedented time skip of well over a century, so we're well and good in the 42nd millenium now. With such a time skip come a few changes: Ursarkar Creed has died of old age and has been succeeded by his daughter Ursula, who carries on her father's legacy and old coat with those who could escape their doomed world and their descendants. Cadia broke before the Guard did. Commissar Yarrick also died, but it's all but stated that he was killed by Angron of all people, so the daemon now has to deal with Ghazghkull coming to avenge his best frenemy.
But Guilliman's gotta deal with his brothers. Magnus the Red and Mortarion have gotten their own models as well in their full glory of Daemon Primarchs, and Angron's model will be releasing soon. A three against one would be bad... except that the Lion also decided to wake up from his nap. That's right, Lion El'Jonson is back as well... if you managed to pick up his model before the scalpers did.
Everybody's trying to adapt to the changes made by the Great Rift. But it's not all about the cosmic bunghole being split open: the Octarius War between the Orks and Hive Fleet Leviathan has seen a decisive victory in the Tyranids' favor. So ol' Kryptman's plan to chuck the Nids at the Orks to have them murder one another, which MANY people warned against, went south because the Nids are now stronger than ever and a massive Ork armada decided to fly to the Great Rift (which they call Gork's Grin, which in their eyes ate the stars and spat out fun stuff for the Orks to fight) to have some fun there. The Nids are gunning for Terra (and for reference, Octarius is somewhere close to Badab on the map) with little in the way to provide a true threat (aside from maybe Catachan). So good job Kryptman, you fucked up big time.
So there's some changes, and it remains to be seen where 10e is going to take us. The core rule book only went on presale yesterday, so I'll keep an eye out for that. So far the Nids look like a big threat, and Cawl finally figured out how to make Primaris Terminators.
It's still grim and dark and there's only war, but it's the 42nd instead of the 41st millenium now.