I've been spreading the Abiotic Agenda in comments whenever I can because I truly love the game that much and want more people to know about it, so I thought a full post was due. In short, Abiotic Factor is a survival game that draws inspiration for its visuals, tone, and setting from the original Half-Life. The entire game takes place in a research facility similar to Black Mesa.
What sets the game apart for me is the Dark Souls/Metroidvania esque level design, variety of locations, and actually pretty solid story and world building. The game has a definitive end point so if you're not into the whole "endless grind" nature of some survival games, this might be right up your alley. The game does let you continue to play after the end though and there are still things to do if you're into just building up a base for the fun of it.
I first played the game when it was still in early access and loved it then. A friend and I restarted the game a few weeks ago now that its been in 1.0 for awhile and I just can't stop thinking about it. The game has a TON of sandbox settings you can modify so if the default balance doesn't quite work for you in single player, you can change just about anything to make it work for you.
Seriously, please play this game. The developers have put an incredible amount of love and effort into the game and I promise it's worth the money. One of the most charming and fun games I've played in a long while and continues to get updates. The team is currently working on the first paid DLC for the game which will come out later this year which will be a day one purchase for me.