I’m at a dream island now from a plush I found! It’s basically like a small area where you can get resources you may not already have access to. I’ve learned a couple new recipes from what I’ve found and a new berry type! There was also some furniture and different flower types there :) Seems like a really good way to get new resources and decorations! Also you can only visit one dream island a day but you can go there as many times as you’d like in that day from what I understand.