Years ago, Nintendo used to hold a show called Space World. It was a sort of Nintendo-only counterpart to Tokyo Game Show, which they didn't (and still don't) attend, where they'd announce new games and consoles, and put them out for the public to play. It had very little to do with space as a concept, but its makes for a very convenient segue into the fact that Nintendo has a crazy shared universe you never knew about, and it all takes place in space. Also, it's all perfectly reasonable and requires no insane leaps in fan fiction logic.
It starts with Tricky, the triceratops prince from Star Fox Adventures. He's best known for being annoying and altogether useless, and also for being the crown prince of a race of space dinosaurs. According to Rare developers though, Tricky actually made an appearance in another game before he was in Star Fox Adventures. An older Tricky happens to be the triceratops who races Diddy Kong and his motley crew of failed cereal mascots in Diddy Kong Racing.
Other than the implication that at some point, the prince of a planet had to seek asylum from a giant pig wizard, that means that the Star Fox universe and the Donkey Kong universe are one and the same. Mind you, the DK universe is also home to the Mario games, so it's more technically the Mario universe, but who cares. It's all one big mess at this point, with plumbers in semi-magical Brooklyn, jabbering monkeys on an island, and chatty animals in space. But how much bigger can we make this Katamari?
Well, Metroid takes place in space, and while that series is pretty against dropping references to other franchises, Kid Icarus isn't. See, Kid Icarus and Metroid are sister games, developed by similar teams and running on similar engines. Kid Icarus Uprising references every Nintendo game it possibly can, but even the original has a little call out to Metroid. The Komayto enemies are just metroids. Straight up, face-hugging, energy-sucking metroids. In Japanese, their name, Kometo, means "little meto", where meto is short for metroid. Assuming those alien parasites are one and the same, we can safely say that Kid Icarus and Metroid take place in the same universe.
Kirby is also a space series, even though it rarely mentions it. Kirby's adventures mostly take place on planet Pop Star, and in Kirby Super Star's Great Cave Offensive, Kirby stumbles across all manner of artifacts from other games. Now, a sane person would take those as just that, references, but I'm here to prove an idiotic point, damn it, and that means I'm going to desperately grasp at any straw I can.
So Kirby can find a whole bunch of referential treasures in the cave he explores.One of them is the "Screw Ball", the item that gives Samus her screw attack ability in the Metroid games. Considering Samus manages to trip and fall and lose her power-ups between every game, I'm gonna go out on a limb and assume it's the same screw ball. Kirby can also find Captain Falcon's helmet, which MUST mean that Captain Falcon was buried somewhere in the caves, and Kirby desecrated his final place of rest.
NOW, Captain Falcon may seem unrelated to all this, but here's where these two threads meet. One of the endings in Sar Fox Command shows Fox and Falco becoming F-Zero racers, bringing those universes together, and by nonsensical extension, every other series I've mentioned so far.
Pikmin's easy to connect, since it's a space series as well, and has references to other Nintendo games. That can stick in the universe anywhere. Punch Out for the Wii features Donkey Kong as an opponent, so Mac and Mario were from the same fictional New York city. One from the Bronx, the other from Brooklyn. It's the fantasy series that are tough to connect, even for an obsessive madman like myself. Zelda and Pokemon are outliers, but there are ways of making them work.
Ocarina of Time features paintings of Mario, Peach and Bowser in Hyrule Castle, likely meant as a cute reference to the painting-slash-warp-gates in Peach's Castle in Mario 64. Those, plus Talon the farmer's Bowser broach could imply that the paintings are connected in some way. We could go that route if we wanted to.
But we don't.
Instead, we'll go out on an even further limb. In Link's Awakening, Link runs across Chain Chomps, Goombas, and a weird, malformed Kirby. I'm gonna roll with that, and assume that one one of the thirty-two branches of the Zelda timeline, Hyrule eventually just becomes Mario's earth, and that what makes that timeline different is that a Kirby landed on Hyrule and opened everyone's eyes to space technology.
Pokemon is more complicated, but stick with me. In Super Smash Bros. Brawl, Solid Snake's mission control already knows about Pokemon. Meanwhile, in Twin Snakes, the Gamecube remake of Metal Gear Solid, Snake can shoot at toys of Mario and Yoshi, implying they're fake in his universe. But Pokemon are real. So the Pokemon universe is one fictional world above every other Nintendo franchise, meaning Pikachu is basically a god compared to Mario and Link.
But we can go further. We can take this to the most illogical extremes we can think of. Ape Escape is canon in the MGS universe thanks to MGS3, and if we take just one more leap of idiotic faith, we can assume that since MGS2's Raiden and Ape Escape's Spike both show up in Sony's Playstation All-Stars, everything in that game is probably canon to Pokemon as well.
So there you go, thanks to Nintendo's (probably nonexistent) crazy shared space universe, Pokemon and Bioshock are probably maybe definitely in the same universe. If you don't believe me, just ask yourself this:
Is not a Pikachu entitled to the sweat of his own brow?