Project Zomboid

Project Zomboid is a zombie survival sandbox from The Indie Stone, still in early access. You land in Knox County at the start of an outbreak and try to last. There is no set ending: the game ends when you die.

You need to do everything: scavenge food and weapons, fortify a house, cook, grow crops, fish and treat wounds. Skills grow with practice, and a single bite usually settles your fate. The rules are highly configurable, so every attempt differs.

According to HowLongToBeat (via DekuDeals), the main time is about 59 hours, with extras about 166.5, and a full run about 433. At about 2 hours a day (roughly 60 hours), a month covers one long story, but not full mastery. To be honest: the rental is offline access, so online multiplayer is not included and you play single-player; the game is in early access and changes with updates.