Hrot
Hrot is a single-player retro FPS set in a small socialist country neighboring the Soviet Union (Czechoslovakia) after an unspecified disaster in 1986. Those times were dark and frightening, and so is the game.
Story
You start out in a civil defense bunker deep beneath a Prague metro station. As a proud bearer of the military readiness badge, you know what your task is: put on a non-functioning gas mask, load the Vz. 52 pistol and protect the peace and your socialist homeland from the foreign invaders.