Very similar to the first game, for better or worse. The original Subnautica was excellent, so, there's a lot to enjoy here. However, Below Zero's new features and story were not enough to sustain my interest all the way to completion, and it is disappointing to see that various UI foibles and graphical glitches are ported over wholesale. I conclude that the first game is the one to play, whereas this one is for enthusiasts.