The listing, Existentia [steam key] has ended.
http://store.steampowered.com/app/511340/
Existentia is a post - apocalyptic adventure with a dark existential ambiance. As one of the few survivors after a nuclear Holocaust explore the ruins of the fictional post-Soviet Republic. You have to learn the history of the world and the people who will never be the same.
Events take place in Artane — island state, which gained independence following the collapse of the Soviet Union just before the beginning of nuclear war.
The lone Ranger, after several months of inactivity decides to continue the journey in the place that once was his home