System Shock (released 1994) was Origin Systems' entry into the first person sci-fi/horror genre, set aboard the fictional Citadel research and mining space station. The player is a hacker hired by an ambitious Tri-Optimum Corporation executive to do a secret hack job on the stations controlling artificial intelligence, SHODAN.
In return, the hacker receives a valuable, military-grade cybernetic implant. However, once the hacker awakes from his post-operation healing coma on board the station, he finds all hell has broken loose. He must fight for survival against mutants, cyborgs and robots created or reprogrammed by the brilliant but insane SHODAN. The story is mostly told through log disks and email messages found and received throughout the game.
Although the game was superficially similar to many other first-person shooters on the market, it was critically acclaimed for having detailed environments, an engrossing storyline and a memorable villain. System Shock is often cited as an inspiration for games like Deus Ex and Half-Life. Even though it was considered technologically superior, it was still outsold by more mainstream action games of the time, most notably Doom. The game sold fewer than 100,000 copies.
The weapons system was considered by some to be quite innovative (for an FPS). Certain weapons affected certain enemies differently, depending on if they were biological (mutants), technological (robots) or biotechnological (cyborgs). This makes certain enemies immune to certain weapons, and vulnerable to others. EMP weapons, for example are devastating against robots and cyborgs, but useless against purely biological targets. On the other hand, gas grenades are effective against weaker mutants and cyborgs, but do not affect robots at all. Some of the tougher enemies are not even hurt by some of the weaker weapons, as the shots just can't penetrate their armour. Some weapons are adjustable, with sliders for the power of energy weapons (also affecting energy usage and heat generation), and for the timers on timed explosives. Most energy weapons also have an overload button, for a powerful (if inefficient) blast. Most bullet weapons can be switched between two types of ammunition, each unique to those guns. A couple weapons are practically useless (in the player's situation), but add to the realism, as they would have been used for stunning of individuals or non-lethal suppression of rioting groups, before everything went haywire on the station.
An unusual aspect of the game is its interface. It was quite complex for a game of the time. Indeed, this complexity may have served as a barrier to entry to some less patient players. However, at the same time, the interface gave a level of control that was not found in other first person games of the time (nor many that came afterwards). Players could duck, and crouch, they could lean left or right, even forwards, they could jump and mantle onto some platforms. Players could also look up and down. The interface had, among other things, three multi-function-displays (MFDs): One in the middle, generally used for inventory, and two side MFDs, which could be set individually to show several kinds of data, such as minimaps, ammunition counts and target information. The player character could also become fatigued from constant running and jumping, needing to slow down or stop to catch his breath.
The bodies of the station crew and destroyed enemies can be searched, and items taken from them. Although System Shock was not the first FPS to have allow a player to do so, it was a very rare feature at the time. Much of the time, these items were randomized, which helps change the gameplay experience each time the game is played.
As the player progresses through the game they find hardware that can be attached to their cybernetic rig, including shields, lights, and mapping and targeting systems. Nearly all of these can be upgraded, with newer versions making them more powerful or offering more features. However, some of these drain power from a main reserve when used, meaning that a player cannot have the luxury of having them on all the time. Thus, the player must balance their energy use, deciding when and where best to make use of the systems. The game Deus Ex makes a similar use of this concept in regards to its Augmentation system.
The player can also find various pharmacalogical patches through the game, each with varying effects, and sometimes negative side or after-effects. The Medipatch can heal, but unlike most games, does so gradually, not instantly. The Staminump patch stops a player from getting tired, but when it wears off, the player is left exhausted. The Reflex Reaction Aid patch speeds up the player character's reflexes (think bullet time), as well as boosting their sprint speed. The Detox patch comes in handy if the player is suffering from biological or radioactive contamination, but also neutralises the beneficial effects (and negative side-effects/after-effects) of other patches, and it stays in the player's system for some time.
The game also contains 'Cyberspace' areas. At certain points in the game, the player can use their cybernetic rig to "jack in" to Cyberspace terminals. The player is then able to fly around a fully 3D user interface, collecting data and fighting security programs. Some actions in Cyberspace generate events in the real world. Some doors, for example, are locked, with the only way to unlock them being accessible via Cyberspace.
There were two versions of the game released. The original floppy disk version was released in early 1994. It only supported one screen resolution, and did not have speech. The CD enhanced version, released some months later, had speech for almost every log and email. It also allowed for several resolutions, up to 640x480 (quite a feat for a 1994 game), including more detailed graphics to make the most of the higher resolution. This was enough to tax nearly any system of the time. The game actually supported much higher resolutions, but these were disabled as they would still have been unplayable years later.