Metro Exodus

Metro Exodus is a survival-flavoured shooter from 4A Games, based on the novels by Dmitry Glukhovsky. Artyom and his companions leave the ruined metro and set off aboard the Aurora train across post-apocalyptic Russia. The journey lasts a whole year, so the seasons change both the land and the threats.

The levels are wider and less linear than in earlier entries. You scavenge materials, craft your own ammo and gas mask filters, and choose between stealth and open fighting. Between locations you return to the train to talk to the crew and prepare for the next stage.

According to HowLongToBeat (via DekuDeals), the story takes about 16 hours, with extras about 24, and a full run about 42. At about 2 hours a day (roughly 60 hours), a month covers everything, even 100%. The game is single-player, so it is fully available under the offline rental.