FOSS gamedev and creative worlds

Anyone played or heard about Subnautica? ''it is an open world survival game in development by Unknown Worlds Entertainment. Subnautica allows the player to explore an aquatic alien planet by scuba diving and traveling in submersibles, while collecting resources and food to survive.''

It would be great if there's a subgame like this on minetest, I'm pretty sure it would be easy enough to create it on minetest with a few mods. I'm not really good at game programming and I can only make a subgame by cutting and pasting codes and combine them together to make it work but I can try making one. But if anyone can make this on minetest, that would be great :D

it would be anice idea, but for the monsters???

gigantic 3d models are not a great idea it does lag! for the mapgen it's easy, it would even be able to do this ;)