The purpose of this node is to point on the similarities between Warhammer Fantasy Battle and Warhammer 40K, both of which are the cash cows of Games Workshop. Naturally, this has been touched on in other nodes - WHFB is to WH40k as a peach is to a nectarine, and vice versa. But never before has it been the subject of careful enquiry, as they are about to be.
Naturally, these prolific creatures are native to both worlds. In WHFB, they are playable as Brettonian and The Empire, with spin-offs including the followers of Ulric and other miniature city-states, and appear in supporting roles everywhere else (except, arguably, Naggaroth and Ulthuan, except as slaves), including the jungles of Lustria, if only temporarily. There are also human tribes in the Chaos wastes, but these really fall under Chaos. In WH40k, they are also prolific and appear playable as the Imperial Guard and Space Marines - although whether they are technically still 'human' remains open to speculation. There are also spin-offs here, but they all fall under the wide umbrellas of Marines or Impies.
In the Warhammer universes, Chaos isn't a mysterious scientific study that makes nice fractal patterns - Chaos is, depending on who you ask, the raw energy of the universe, the embodiment of evil, or the playground of the Gods of Chaos. These Gods come in four flavours - Tzeentch, Khorne, Nurgle, and Slaanesh. The fact that these Gods are common to both universes is a big hint for those that didn't notice that both are called 'Warhammer'. In WHFB, these come in the flavours of Followers of Chaos, Beasts of Chaos and Daemons of Chaos, while they are known in WH40k as just different components of the all-encompassing Chaos Space Marines with spin-offs of the Traitor Legions.
Orcs and Orks
What can I say that isn't immediately obvious? Both are green. Both are lacking in the brain department. Both like blowing things up. Both have smaller green flunkies - goblins for the WHFB, grotz for the WH40k. Both worship Gork and Mork. The only real difference is the amount of technology they have.
Elves and Eldar
Starting to get a little less obvious, but only a little - the names are similar, the ears are a dead giveaway, and their holier-than-thou attitude is universal. Universal to the High Elves/Vanilla Eldar I mean - you can tell a Dark Elf/Dark Eldar by the way they just enslaved you. High/Vanilla versions tend to travel around being mysterious and following a strange plan only they have wont of, and have the ability to manipulate magic/the warp greater than almost anyone else. Those of the darker shades tend to be dedicated to either experiencing pleasure while causing pain, or dedicated to Slaanesh with the same results. The Wood Elves, however, seem to have missed the transfer. Or maybe they're just hiding on Catachan somewhere - plenty of woods for them there.
Dwarves and Squats
Dwarves are Tolkienish WHFB short folk that are good with technology, dangerous with axes, and have underground mines that go for depths unplumbed. Squats are midget miners that have either, depending on your opinions, have been pruned from the WH40k universe due to disinterest, or for, um, other considerations.
Ogres and Kroot
Now we're going into the less obvious territory. Ogres are big fat bastards that cost a truckload and have the ability to smash their way through enemy lines, while Kroot are Tau bullet shields. But why do Kroot fight? Because they are mercenaries, and they believe that eating their enemies makes them stronger. Why do ogres fight? Because they are mercenaries, and they believe that eating their enemies is a method of worshipping the Maw, which makes them stronger. Case closed.
Tomb Kings and Necrons
This is a bit less obvious, but both boil down to - ancient mysterious structure from an ancient mysterious civilisation, head honcho awakes or gets awakened, gathers together an ancient army and starts to attack all in sight. The only difference is that the Tomb Kings have mummified princes, kings or priests leading the ranks, while the Necrons have something called a C'tan. The Tomb Kings are hard to kill because they just get up again, while Necrons have a handy-dandy self repair system. All in all, a fair match.
Undead and Tyranids?
This matchup is the one I have most trouble with - sure, they both want to convert anyone and everyone to their way, via necromancy or recycling, but the two really don't mesh. Undead in WH40k has been delegated to Nurgle and the Zombie plague, and features as just an add-on to the Traitor Legions and a random encounter or two in Necromunda. Tyranids, however, just don't fit into the WHFB world, because it would probably end with the races uniting against them or getting wiped out. One planet just isn't big enough for Tyranid-esque races.
Skaven have no direct equivelants in the WH40k world, although there are Necromundan Giant Rats and various small and furry aliens that could fit the bill. Games Workshop has at various times toyed with the idea of Space Skaven, but none of these have gone official. There are, however, examples of third party codicies on the internet if you search for them. The thought of a Ratling Gun crew getting it's furry hands on a plasma cannon is just too beautiful to leave alone.
This is where the matches wear out. Depending on which you prefer, the skinks and saurus were either created or tamed by the Slann. The Slann are in some way linked to the Old Ones, which created some sort of gate at the North Pole which went explosive with tragic results and either caused or unleashed Chaos, Magic and Warpstone. This leads to a few tentative guesses. Option 1, the WHFB world is a planet in the WH40k world which had some sort of astronavigation beacon go boom at the Pole. This means that the Slann are somehow related to the Adeptus Mechanicus or something else along those lines. Option 2 is that the WHFB world is set in the Dark Age of Technology, before the Emperor started up the Empire, plunked his Holy Behind on the big throne and started sucking up Psykers. Option 3 is that they're unrelated and Gee-dub hasn't got enough imagination.
Tau. Well. The only halfway-close match I can think of is Halflings, and that only due to physical size. Comparing a race of hairy-footed freaks whose greatest contribution to warfare is throwing soup with a race of four-fingered munchkins that fought off a fleet of Space Marines (with assistance from a warp storm) and invented the pop-up cheese-bot, otherwise known as a Crisis Battlesuit.
Whether the links are intentional, a result of imagination withdrawl, or a cheap ploy to get people talking about it, they are there. Be aware of them, because if you mock someone for having High Elves in 40k and they turn out to be Eldar, you can never show your face again at that location. And no, that didn't happen to me. Really.