BioShock 4 has been officially confirmed as in development. Though nobody knows how far along the game is, the newly-formed Cloud Chamber studio is definitely working on BioShock 4, though it's still years away.
The only real thing known is that it is, in fact, a BioShock game, complete with first-person-shooter gameplay intact. While the gameplay of the BioShock games is definitely well-crafted, what draws many players into the franchise is the world itself. BioShock is a series that creates visually stunning, imaginative, and philosophically-charged worlds that challenge player's conceptions of the world, society, and their place in it. A setting/story-type that would be a perfect fit for BioShock's brand of storytelling and worldbuilding would be a setting that's been around for a long, long time: the Western.
The Settings Of BioShock
What makes BioShock a franchise with ludicrous potential is the fact that this kind of world can be crafted in just about any kind of setting. BioShock 4 will likely keep this hugely important feature, it could still do some very new things, especially considering how long it's been since a BioShock game has released. The series has already explored two incredibly different settings in both Rapture and Colombia; worlds that have enough similarities to cement them as BioShock settings, but are different enough to give the games their own unique feel. The worlds in these games are, at face value, polar opposites.
BioShock's Rapture is an undersea, neon-infused city in a state of perpetual nighttime. It's a society that rejected the idea of viewing society as a group, instead focusing on the Ayn Rand style of philosophy where each person acts in their own self-interest. There was no big-brother oversight, allowing art, science, and capitalism to roam unchecked. This led to a societal collapse, leading players to the conclusion that people acting in their own self-interest, unchecked, are going to end up hurting others for their own gain.
Colombia takes this philosophy in the other direction, using religion as a way to attempt to unify people (or, in this society's eyes, the 'right people') under a common goal. This is a very broad generalization of Infinite, as there's a lot going on with the main character here. But, simply in regards to the setting, that's the gist of it. This is another society that has gone a full ten out of ten towards an idea, and another society that fails in a huge way because of that. BioShock 4 could follow Infinite's lead away from horror, as the Colombia setting was not as outwardly frightening as the city of Rapture, though the game still did have its moments.
The Structure Of A Western
While obviously not every Western is the same, most of them contain many of the same thoughts and ideas about individuality, as well as society as a whole. Westerns generally contain a main character that is resistant to the changes in society. Right or wrong, they hold old-school values that serve as the basis for their actions throughout the story and serve as the basis for how the evolving society treats them. Usually, the main character comes up against a form of antagonism that only they can successfully oppose, as the antagonism hits the society in a specific way that they cannot cope with. The main character either succeeds, or fails, because of the values they hold that are different than that of the society around them.
What Would A Western BioShock Look Like?
Looking at how BioShock generally deconstructs a philosophical argument that's been pushed to the max and looking at how the usual Western is structured, it's possible to see what a Western BioShock game could possibly look like. It doesn't necessarily mean that the BioShock game would have to take place in the time period of most Westerns, or even in the American West; it just means that it would be a story and world that has a similar artistic style and themes. It'd be a really easy way for BioShock 4 to introduce a new setting.
A BioShock Western would need some kind of glue that holds the society together, a glue that's been pushed to the max, in order to fit into the BioShock series while also fitting into the Western genre. The antithesis of this glue, then, would be the form of antagonism that the society faces. This would be a great way to examine two mirrored philosophies in the same game, and depending on the main character's role, it could set them both up as antagonistic to the other instead of a black/white morality where one side is good and one side is bad. Red Dead Redemption 2 did something along these lines, with Arthur and the Dutch van der Linde gang performing in the morally grey to occasionally straight-up morally black area (somewhat depending on how the player plays).
The main character, then, would need to be someone that doesn't necessarily fit the values of the general society, but also doesn't quite fit into whatever form of outlaws this world holds, either. Westerns usually have a heavy emphasis on justice, just not a justice that the system can provide; a form of justice only someone from outside the system can provide. If the main form of society is shifting towards law-and-order/authoritarianism, and the outlaws are anarchists, then the main character would need to be able to experience both points of view from somewhere in between.
With the possibility of two philosophical arguments in a Western BioShock, it could also put player choice further into the equation than BioShock ever has before. Huge, world-changing decisions could be made by the player, depending on which side (if either) the player decides to choose in different scenarios. Admittedly, it could be difficult to provide the same narrative experience that the BioShock games are known for if there's an overabundance of player choice, but games like The Witcher 3 have proved that it is possible. Plus, there's a BioShock 4 job listing hints at more RPG elements.
Regardless, it would be exciting to see how the BioShock series would treat a Western. The series and the genre seem to fit so well together; maybe the reason it hasn't happened yet is because it almost fits too well. BioShock has always created worlds that are somewhat shocking, and with it being so easy to see how BioShock could work as a Western game, a genre that already deals with philosophical questions on the regular, maybe the developers decided that it would be too predictable. Either way, BioShock 4 has tons of potential, and fans are excited to see what it's all about.
BioShock 4 is in development.