What surprised us most during our demo was exactly how well Irrational has managed to map the gameplay concepts of System Shock 2 onto this totally different, totally unique and original new setting. Levine says the team basically wants to give the player far more to do than he or she can handle in terms of abilities, paths, and general options for tackling a given situation. Thus BioShock holds the same promise of open-ended scenarios that can play out in surprising and delightfully random ways based on how you choose to make use of your myriad available tools.

The free-form character building seen in Shock 2 will also make its return here. But where Shock 2 had nanotech-enabled skill upgrades for your futuristic soldier, in BioShock you'll gain "plasmids," which are biological augmentations that function in essentially the same way. Your plasmids will be interchangeable, so you can run with a few powers for a while, then swap some of them out and try others at the next opportunity. Those opportunities will come, at least in part, when you find one of the cheekily named "Plasmi-Quik" machines mounted on Rapture's walls, evidence of the highly capitalistic society which are accompanied by sickeningly cheerful branding that must have been used to sell the plasmid lifestyle to the city's inhabitants before their downfall.
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At the risk of hyperbolizing, or sounding like the fanboys we are, or whatever, BioShock is basically everything we hoped it would be, given its lineage. The game looks to capture and improve upon all the gameplay elements that made System Shock 2 so compelling, and it looks and sounds great (and unsettling) doing it. Just as exciting was Levine's description of the game as being all about choice--not just choice of gameplay, but choice of morality, as you'll be faced with difficult and ambiguous choices minute to minute. We're awaiting further details on BioShock with unfettered zeal, and we'll bring them to you as soon as we get them. Stay tuned.​

Irrational mentioned they're focusing more on interesting, emotional enemy A.I. rather than advanced squad tactics. Like with the Big Daddy, we're to expect lifelike, authentic behaviors rooted in more complex motivations than blind, murderous rage. Another enemy type we saw, the Splicer, was much more aggressive than the cumbersome Big Daddies. These enemies hopped around erratically, sometimes stood on the ceiling, and slashed around hooks on the ends of their hands. Capable of quick charges, the Splicers were the biggest threat encountered in the demo. These mangled female forms in ratty green robes had abused too many of Rapture's genetic enhancements, driving them nuts.
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To combat these fierce foes, only had one weapon was available. Best described as a shotgun, the weapon was a cobble of rusted cans, spare parts, and cogs, making for a uniquely rudimentary yet attractive piece of machinery. All of Bioshock's weaponry can be modified, making it useful against a range of targets. This particular weapon took two kinds of ammunition that we saw: armor piercing and anti-personnel. Whereas the armor rounds were effective at wiping out mechanical enemies, they were frustratingly ineffective against the Splicers. It took about six or seven shots to cut up a Slicer with armor rounds, whereas it took two to shatter its life with the antipersonnel variety. When playing, players must exploit strengths and weaknesses like this to help conserve ammo, of which there's far from an inexhaustible supply.

Further into the demo Irrational entered a bar, flipped on the lightswitch, and was immediately shot at by a standing turret gun. Like the shotgun adorned from cans, the turret was equally rudimentary; a desk chair with a machine gun roped to it. Taking cover behind a bar, it was possible to grab a few bottle off the counter to replenish health. A downed register yielded some Adams. Like those objects, almost every item in Bioshock's game world can be inspected or interacted with, adding to the immersion factor. To escape the turrets deadly fire, it was possible to initiate a speed burst implant, sending us flying across the room to an open door, and safety. At the stairway's end some armor piercing shells were found, which were highly effective at taking out the turret gun.​