Currently only undertales_3000, Explosions_Central, ashheart567, and theblueninja can join. It is like this for saftey. If you are not one of the users listed above, try joining and see what happens! You can change the volume with the volume slider, and the opacity of the rainbow background with the rainbow opacity slider (0-25 is recomended for those who are prone to having seizures). You will also need to refresh a lot.
Once I get a moderator, everyone can join. THIS PROVES THAT MULTIPLAYER CAN BE DONE IN 3.0!!!!!!!!!!!!!!!!! (Everyone already knows that, it's just that the most common way for multiplayer stopped working in 3.0, but ther are still many other ways {like the one that I am using...}) Music is Fluffing a Duck by Kevin MacLeod, but I made it faster. Someday I could use this kind of method for auctual multiplayer games. If I ever do, the link will go here: ___________________________________.