Players will be able to invite up to three others into their world, each taking the role of a farmhand, with the ability to do most things the main player is able to do.
Unfortunately, you'll be stuck waiting a while longer if you were hoping that Stardew Valley'smultiplayer mode would release this year. Your friends will play in your game as farmhands, and they'll be able to do pretty much everything the host player can do.
Stardew Valley is one heck of a popular life and farming simulator and this year it's getting a big update in the form of multiplayer.
Adding friends will involve having Robin build farmhand cabins on your land. Farmhand characters can do nearly anything your main character can do, including marriage, participating in festivals, and various farm tasks. All four of you can farm, mine, fish, forage, marry NPCs and so own, with independent inventories - these can be managed by other players when someone is not connected. Friends can be invited onto the farm through Steam. Marrying another player won't require the mermaid pendant, but you'll still have to put in some work with an undisclosed alternative method. However, they've made it clear that local multiplayer, split-screen multiplayer, and player versus player multiplayer are not in the works for the game.
The work so far has been focused on the "biggest technical hurdle" of synchronizing multiple games over the internet, and it has apparently been a huge job: Chucklefish said that 15,000 lines of code have been rewritten, and nearly every source file has been impacted. The developer took to their blog recently to outline their plans for multiplayer in the game, which includes a beta test in the near future.
A beta test will be run for Steam users toward the end of the year, followed by the official 1.3 patch for PC, Mac, and Linux early next year. There's no time frame for when the PS4 and Xbox One versions of the patch will be released, though Chucklefish notes that it will "take a while to roll out to each platform".