Stardew valley, like the harvest moon series it is descended from is a 2d action rpg. Only instead of setting off to save a princess, or to collect four crystals, your goal is to save a farm and build a community. The game is an excellent example of how simple mechanics can be used to give very different experiences. Calling it an action rpg will probably cause some heads to swivel, but the basic mechanics have been with us since the legend of zelda.

Where stardew valley succeeds for me is in the heart it has. Every one of it's characters is crafted with strengths and flaws. The town is lovingly realised, peoples relationships aren't always smooth, and a lot of the interpersonal conflicts are products of lack of communication and emotional reaction. This means that the town feels alive and present, the stories that occur there have a little more depth than the cutesy presentation might initially insinuate, and that cutesy presentation itself is lovingly realised, speaking to an immense amount of care poured into crafting the game.

The farm and your ambitions for it put limits on how much time you have for other aspects of the game and this allows a player to find the balance that's right for them, and no matter how it balances the other parts of the game are present enough that it can constantly feel like the player is juggling different demands. This makes the urge to play "one more day" quite compelling.

If you've never played a game like this, Stardew Valley is probably the best in the genre. A great place to start if you're interested. If you played and enjoyed old harvest moon games, this will be very familiar and enjoyable.