Games Workshop are not above allowing some leg room and neither are most of the fan base. And they clearly state this. So I am fine with it., truth is the developers themselves have stated they don't personally like having to deviate more than they have to. Being a purist to the lore is silly, because Games Workshop radically change their own lore for Warhammer 40 000 every 5 to 6 years based on the history of how they market their game. Some say it's for the better, some say it's worse. Personally I feel when you have a dozen different writers working on the same material all applying their own personal opinions to how they feel Warhammer 40 000 should be like randomly at different points in time, some lore ends up being very clear, while other aspects are left very vague. For example, for a very very long time, the good first 3 years of the life of Warhammer 40 000 the section on the events of the great crusade and the Horus heresy were left up in the dark by Games Workshop, confined to a few paragraphs in the first rule book. After that they decided to slowly expand on this, brought out a game based on it, then after that again left it alone for many years until around 1998-ish where they decided to fill it out and now we have a lot of info on that time period, enough said info that lore buffs can watt their booksticks at us for getting any of it wrong. But we also have the case where GW writers completely re-write the lore, such as in the case of Sisters of Battle, Tyranids and Necrons. And people were never happy with what they did, but that's the lore of the game now, like it or not. Least the person who changed it is now no longer allowed direct control over writing codecies. And also the game history itself has changed, back in 2000, the timeline was building up to a point of the collapse of the Imperium, all the signs pointing towards it. However since then Games Workshop has slowly steered the course of the game away from the end time being in .M43 because they don't want the story to end there. The lore is a complex constantly shifting and changing thing... and purists make a sook about it all the time. Heaven forbid we have the same amount of stupid fanboi'stic nonsense Star Wars suffers from, where if Lucas changed anything everyone thinks he betrayed the fans and turns their back on him. And now even that is out of his hands, he sold Star Wars...
Close is better, as close as possible without a great breakdown of lore would be great. I don't see this game being so story focused that we would be concerned, but I hope I do find lore objects to read that have tons of accurate information on them in game.
as long as it plays well, and you feel like all the story behind it is there, even if its not exact, then all is good... if it were all to fit to what supposed to be what, then it wouldn't work at all. after all what fun would battlefield games be, if the Non-US forces were actually as underpowered as they are in real life, it would be no fun playing as that side, they don't have 100's of helicopters with heat seeking whatever... but in the game they doo, cuz without, it would suck!
As close as possible please, or I'm going to have to make explanatory videos explaining why they decided to make the Tyranids fluffy (for eg).
So long as it's nothing crazy. "LOL haha it turns out that Lion 'El Johnson was really a heretic" Look at Space Marine, even that game had it's stretched sides. But yeah, just nothing crazy and so long as it adds to the total experience I'm cool with it.
From an interview with Aaron Dembski-Bowden (emphasis added): I'm as much of a fan as anyone. I live and breathe Warhammer and Warhammer 40,000. I love it enough to make it my career, as well as my main hobby. But once you're 'behind the curtain', so to speak, you realise a lot of fan assumptions about how the license works are just that: fan assumptions. Games Workshop is very, very careful with its licenses. That's not to say mistakes don't happen, because mistakes always happen in any human endeavour. A three-second glance at any site listing the hundreds of errors in any movie's production will tell you that. But Games Workshop shaped Warhammer and 40K to be open to interpretation, because a massive chunk of the hobby is bringing your own lore to the table. "Canon" doesn't really exist in Warhammer 40,000. Not as it does in other licenses. The very point of the setting is to offer some structure, then open it up to personal interpretation. Yeah, there are hard and fast rules. A Chapter descended from Rogal Dorn's gene-seed is unlikely to ever develop a Betcher's Gland, given it's not in their implantation process. Because of that, as an example, the Black Templars can't spit acid. We know that. But the setting is set up with countless holes for your own army background and lore perceptions to neatly fill. The battles listed in every Codex aren't the only battles and characters - they're not even all of the major battles and characters. They're examples, taken from a spread of ten thousand years, across countless millions of worlds. They're slices of lore to use wholesale, or peel bits off and use as examples. These are future histories. It's all already happened, but the reports we get from that far-flung era are unreliable, corrupted by distance and time and a billion unreliable narrators who know a fraction of what the rulebooks tell us. Games Workshop actively encourages that attitude - the idea of everyone coming to 40K and seeing something slightly different: the same thing from a different angle. An author can say Character X was on World Y in Year Z, and another author might contradict it in something else written several years later if he or she has a different idea. Choose which you prefer? Assume both are false sightings and Character X was nowhere near either world? It's your call. That's the point. There is no canon. There are several hundred creators all adding to the melting pot of the IP.