Subnautica is one of the hardest things I've written, for all sorts of wonderful reasons. The world is huge and open, so pacing is out the window. There aren't other people wandering about, but human characters are the most interesting way to tell a story. We have huge creative freedom and independence, and a passionate fan-base with firm ideas about what the game is.
I was asked recently if I could share some of my process on character development for it.
That's a bit like watching a man fall down a hill chasing a rolling cheese, then asking him at the bottom how he did it - it's a lot of pain, hand-waving and muscle memory - but I'll try.
Spoilers for SN1 throughout.