Crossovers happen in games all the time. Capcom fighting games have been at it for years, and SoulCalibur has taken the idea to ridiculous lengths (Kilik vs. Darth Vader, anyone?). But that's not the stuff we're talking about here. That stuff never approaches canon legitimacy. It's just gimmickry and marketing. No-one ever thought that the Battletoads really lived in the same world as Billy and Jimmy from Double Dragon.

No, what we're talking about in this feature are the cooler references. The ones that imply that two disparate games are part of the same narrative continuity. And we're skipping the obvious ones, so no Street Fighter and Final Fight, or Ninja Gaiden and Dead or Alive here. There's much more interesting stuff to be discussed.

Almost all of id Software's stuff

Wolfenstein 3Ds hero was one William B.J. Blazkovicz. After the war, William settled down and had a son, Arthur. And when Arthur eventually had a kid, he named him William after his grandfather. That particular William Blazkovicz went on to be known by the pseudonym of Billy Blaze. AKA Commander Keen, star of ids first ever series of games.

But lets not leave Wolfenstein behind just yet. You see at the end of the Wolfenstein RPG spin-off, Blazkovicz encountered and defeated a huge demon known as the Harbinger of Doom (you see where this is going, right?). He beat it by blowing off one of its arms and one of its legs. Upon defeat, the demon told old grandad Bill that it would return to face off against one of his descendents. So, coincidence that Dooms Cyberdemon has a robotic arm and leg? Not at all. Oh, and in the following Doom II RPG, one of the playable characters is another Blazkowicz, this time a Marine called Stan, who may or may not be the original Doomguy.

The Quake link? Doomguy appears in Quake III Arena as a playable character. Though given that Quake III seems to occur in a separate plane of reality all of its own its maybe more a case of two games set in the same multiverse.

Kane & Lynch and Hitman

There was a subtle hint that IO Interactives best loved and most maligned franchises might exist within the same continuity way back in 2006s Hitman: Blood Money. Despite the fact that Kane & Lynch wouldnt be released for another 18 months, the reference to a pair of escaped bank robbers in one of Blood Moneys between-level newspaper reports was, in hindsight, a feasible nod to the then-upcoming game.

The links are made even more explicit in Hitman: Absolution. You see both Kane and Lynch are actually in it. Kane turns up in a bar, and later in prison writing a letter to his daughter Jenny. Lynch can be found going mad with a shotgun in a gun range. And, yes, should you be one of those Hitman fans whove spent the last five years cursing IO for concentrating on the wrong franchise, you can gain a bit of catharsis by killing the crap out of them. Never let it be said that IO dont listen to their community.

Ultima and Wing Commander

Seriously. Origin Systems two biggest classic franchises exist in the same universe, despite one of them being a medieval fantasy RPG and the other being a narrative-driven space combat sim (though admittedly Ultima 1 had its own space shooter section towards the end. For some reason). Anyway, at one point in Ultima VII, its possible to find a farmer with a very strange story indeed. You see one of his fields has more than just potatoes planted in it. It also has a rather conspicuous crashed star fighter sitting awkwardly in the corner.

And in case there was any doubt as to the origin of said space-bound sore-thumb, its discoverer also claims to have met its owners. Big, mean, ugly liontigers!, apparently. Or is that tigerlions?

Either way, thatll definitely be Wing Commanders enemy race, the Kilrathi, that hes referring to.

SSX and Burnout

This one was confirmed as soon as Burnout Paradise started up. Those of us who played (or lived in, as is a much more applicable phrase to those in the know) SSX 3 let out an immediate air-punch of jubilant recognition as a voice hard-wired into our brains immediately greeted us. Burnout Paradise, you see, is narrated/commentated/guided by DJ Atomika, mouthpiece of Crash FM, replacement for Burnout 3s DJ Stryker, and former main man at Radio Big.

What is Radio Big?, you might well ask, if you havent been paying attention to the words on this page thus far. And the answer to your question would be The local radio station of Big Mountain, setting of SSX 3. Atomika even directly references the series at one point in Burnout Paradise, mentioning an e-mail from SSX stalwart Mac Fraser regarding the state of the snow on the mountain. The e-mail said that the mountain would be ready for riding that winter, which obviously whipped fans up into fervour in the real world. The new SSX finally came along four years later and wasnt set on Big Mountain, but hey. At least it came along, right?

Now lets have Atomika back in the next SSX. As fun as the crazy Russian one was, those helicopter pilots were no replacement.

Bomberman and Lode Runner

Sort of. In the NES version at least, its revealed right at the end that not only are both 80s classics set in the same universe, but Bomberman himself actually is Lode Runner.

A bit of background. The 1985 NES version of Bomberman was made back in the days when people still cared about Bomberman having a single player campaign. The ultimate objective of that campaign was for Bomberman to bomb his way out of the subterranean factory he worked in, climb to the surface and become human. Ignoring the obvious socio-political subtext, the interesting point comes when you consider that Bomberman creator Hudson Soft had also created the NES port of mine-based platformer Lode Runner in 1984. In fact Bombermans now-default 1985 character design had actually derived from an enemy sprite in the previous game. Cementing the connection in the games end sequence, Bombermans human form turn be Lode Runner himself, adding a deft plot twist as well as a cheeky advertisement for the other game.

Way to go, Bomberman. You escaped factory work to slave away in a mine. A mine filled with enemies, in which you are now fleshy and vulnerable. You have won.

Grand Theft Auto, Manhunt and Bully

The link between Grand Theft Auto and Manhunt isnt too hard to find. Manhunts Carcer City is referenced in the GTA series multiple times in dialogue, shared company names, car number plates, airport arrivals boards, and TV and radio reports.

Bully though? Not so obvious. The main link comes in Grand Theft Auto IV. One of the games watchable TV shows is called Im Rich!, and is a parody of shows like The Fabulous Life of and Lifestyles of the Rich and Famous. In one episode it directly references Bullworth Academy, the school around which Bully is centred.

Theres possibly another, less definite link too, this time in Bully itself. The games Blue Skies Industrial Park contains a house that has long been a point of contention regarding a potential Manhunt link. When standing outside its possible to hear (admittedly ambiguous) noises from inside, which many have interpreted to be a combinations of a revving chainsaw and a porcine grunting. They could also be someone snoring with the TV on in the background, but if the former interpretation is to be believed then the sounds could indicate the presence of Piggsy, Manhunts rather grim boss character. The appearance of a drawing of a pig in the nearby asylum has only bolstered the theory over the years.

Final Fantasy VII and Final Fantasy X

That rule that differently numbered Final Fantasy games exist as entirely separate entities rather than direct sequels? Not exactly a hard and fast system. You see Final Fantasy X and Final Fantasy X-2 are very, very distant prequels to Final Fantasy VII. The evidence? Final Fantasy X-2s Shinra.

Shinra is a technical boy-genius, and the creator of the games Garment Grid system, But he had a much greater scientific ambition. Recognising the Farplane (Final Fantasy Xs afterlife) as a potential source of limitless energy, he aimed to eventually harness it in order to power the planet. Given that the Shin-Ra Company in Final Fantasy VII had exactly the same plan, wishing to draw Mako energy from the Lifestream, doesnt all of this smack of a little more than coincidence?

Series writer Kazushige Nojima has even admitted the connection, stating of Shinra in the Final Fantasy X-2 Ultimania retrospective book,

he is unable to complete the system for utilising this energy in his generation, and in the future, when travelling to distant planets becomes possible, the Shin-Ra Company is founded on another world, or something like that....... That would happen about 1000 years after this story, I think.

So, can you think of any more we've missed? And no, Smash Bros. does not count. While you're pondering, why not check out some of our other articles on what happens when franchises collide. 9 Disney / LucasArts crossovers that need to happen and The 15 most bizarre crossovers in gaming come particularly recommended.