Space Station 14 is incredible. Absolutely the most fun I've ever had playing any sort of multiplayer game. And since it's open source there are dozens of servers running their own forks, and lots of features or mechanics or improvements spread across the community when they work out well in their particular forks.
Basically, it's Among Us on steroids. Dozens or a hundred or two players all working to keep a space station running, except for the few randomly selected antagonists with goals to kill certain people, steal certain items, blow up the station, demonstrate wizardry prowess by conjuring wedges of cheese, turn people into intelligent corgis...the list is endless.
Bit of a learning curve but it's so worth it, each department has such depth to it and they're all so much fun to learn.
And the culture is just so wonderful. Folks are SO eager to help out new players. It's always so exciting to meet a newbie who's joined.