This may be surprising, but Subnautica is my comfort game, even though the game isn’t purely relaxing and has some scary parts. But the gameplay loop is so satisfying, the story is nice even after several playthroughs and there is beauty in these alien underwater biomes. I just wish it was longer, now that I know where to find what, it gets quite short :)

Second comfort game is Terraria but I also play that for entertainment/when I feel a rush of creativity for building stuff. And it’s just so nice to dig your way through a large world and find all the hidden items.