People have asked this question a lot in the past. Now, I don't know if these people are new, or is they didn't see the articles of anyone else asking this, but Monomi Park has stated in a forum topic that they will not be making multiplayer anytime soon.
Nick wrote:Will Slime Rancher support multiplayer?
Since we're seeing a lot of requests for a multiplayer feature from all our new (and awesome/handsome/beautiful) players, we thought it would be a good idea to address it.
Most of Slime Rancher's development was done by two people so a lot of decisions were made early on to allow two developers to make a game in a realistic timeframe. One of those decisions was multiplayer vs singleplayer.
Multiplayer is inherently more complicated and time-consuming to develop. And the hundreds of physics-enabled slimes bouncing around on screen needing to be in sync across two or more clients is a fantastically difficult problem to solve. So we decided to focus on solid single player experience.
For this reason we currently have no plans for multiplayer. However, anything is possible in the future if we continue to see the same level of wonderful support from players as we do now. So thanks for everything so far!
Now, not trying to shoot down anyone's dreams, but the devs just can't see this happening right now. And again, not saying this is a terrible idea, it just has "a fantastically difficult problem to solve." Case closed.
Okay, that's it.
lol bye