IGN AU: At various times in its development, the game has been described as an RPG, a shooter, a sandbox game and everything in between. It's obviously one of those new-fangled genre-mashers. In your words, describe the gameplay mix for us - is it mostly blasting? Much puzzle solving?

Jon Chey: Actually, this is pretty simple: BioShock is a shooter. It's true that it is doing things that no other shooter has done before, and that gets people confused about what genre it is. It's funny how genres work. They certainly help people figure out what games are and help them decide whether or not to pick something up and try it out. But at the same time, they often act like straightjackets. Developers get lazy and just follow conventions. I mean, why does every shooter have to go in a straight line from where you enter the level to where you leave?

GTA asked questions about what it means to be a driving game ("why do you have to go round and round a closed track?") and that turned the genre on its head. We're trying to do the same thing for the shooter genre by adding non-linear exploration, choice of tools, deeper interactions with AIs and so on. But at the end of the day, you've got to be able to aim and pull the trigger. This is a shooter.

IGN AU: What does BioShock do that the System Shock games didn't?

Jon Chey: Oh God. Well, start by go taking a look at a BioShock screenshot. And put a Shock screenshot next to it. I love Shock 2 but it's kind of hard to claim it was pushing the visual boundaries of game development. I think that is a claim we can make with BioShock.

And then there's physics and environmental simulation. BioShock lets you set people on fire. And then if they bump into something flammable that catches on fire too. Or you can light pools of oil and watch the fire spreading down the hallway. And AIs that are on fire can jump into a pool of water and extinguish themselves.

And what about AI? Big Daddies pick up Little Sisters and carry them around on their backs to keep them safe. Splicers run to health stations to heal themselves when they get damaged. I don't remember that stuff happening in Shock 2.

But perhaps more than anything else, these just aren't the same games. System Shock 2 was an FPS/RPG hybrid and it felt that way when you played it. BioShock is a deep shooter. It just feels different. We have designers and programmers just focusing on movement and aiming, getting the feel right. It's the same thing that every great shooter has to do but we didn't have time for in Shock 2. It's probably not clear from screenshots or movies but it's pretty obvious when you pick up your mouse or controller and start playing.