Cytadela
An old-school first person shooter from classic Amiga computers
..., as the only survivor, have no other option but to fulfil the mission on your own - you have to destroy the Citadel. In order to do that you have to penetrate the whole base, find six parts of a bomb and plant it in the Command Centre. Your task is by no means simple - there are hordes of enemies who will try to stop you, and you will have to solve many riddles in order to find your way through the base.