We strongly recommend that you buy the game so you can support the developershttps://store.steampowered.com/app/264710/Subnautica/
WHAT IS SUBNAUTICA
Descend into the depths of an alien underwater world filled with wonder and peril. Craft equipment, pilot submarines and out-smart wildlife to explore lush coral reefs, volcanoes, cave systems, and more – all while trying to survive.
HOW DO I INSTALL SUBNAUTICA ?
1. Click the green UploadHub button and you should be redirected to the Download.
2. Once SUBNAUTICA is finished downloading, extract the .rar file. (You will need WinRar, you can get it here
3. Once its extracted, go into the games folder and right click the game and run it as administrator and Enjoy!