While continuing its work on Sea of Thieves, Rare is developing a brand new game called Everwild. What is Everwild? Well, it's a vocal track with lots of "oooh-eee-ahh-oooohs," a band of adventurers, and some very cute, No Man's Sky-looking animals. One animal looks less nice (you can tell because it emerges from a shadowy cave), and presumably you will fight that mean animal.
Otherwise, we really don't know anything about Everwild. It's a nice-looking trailer, though it doesn't get the imagination going in the way Sea of Thieves did when it was announced. It's a forested world with some cute animals in it, and presumably multiple players. I've seen worlds like this before—in Monster Hunter or Dauntless, Shelter, Breath of the Wild, and so on—so the art alone isn't enough to sell me. I want to know what we're doing in this world.
Maybe Rare will announce more soon. In the meantime, get your fill of "oohs" and "aahs" in the trailer above.