Marines specialize in combat, navy officers can repair weapons and hack computer terminals, and OSA agents may begin the game with psionic powers. This choice grants bonuses to the protagonist's initial skills. In the beginning of the game the player chooses a career for the protagonist in the UNN.

System Shock 2 is a hybrid of first-person shooter and role-playing game. His first task is a rendezvous with this woman, for which he will have to traverse the monster-infested corridors of the ghost ship. The soldier is contacted by a woman who identifies herself as the only human survivor. It appears that both ships were infected with something so horrifying that nearly the entire crew was either killed or mutated into monsters. However, the next thing the soldier can remember is waking up in a cryo-tube on the Von Braun. This ship's duty is to escort the Von Braun, an experimental faster-than-light starship, on its maiden voyage. In the year 2114, forty-two years after the events described in System Shock, a soldier joins the military organization Unified National Nominate (UNN), receiving the number G65434-2, and is shortly thereafter assigned to the military space ship Rickenbacker.

System shock 2 full walkthrough