So many mammals like in caves and burrows, and I think they would make the game a lot more interesting. They would be small (2-5 spaces) and would give warmth in the cold islands. Maybe if it snows the animals inside would get snowed in and have to use a turn digging out. Maybe animals with the digging ability can build a 3 wide triangle underneath certain types of trees. Also the caves can serve as a way to protect babies from things like bearyeenas. If a nicheling stands in the entryway, then