Avorion

Avorion is a procedurally generated sci-fi sandbox where players start out at the edge of the galaxy and must find their way to its core. Players build their own ships, which they will use to explore the galaxy, trade and fight. Space ships are mainly of large scale, with crews, turrets and energy systems that you will have to manage. The galaxy gets more hostile, but also more rewarding the closer players get to its core. You're free to play however you want, as a mercenary, freighter captain, admiral, scavenger or pirate, it's all up to you.

A few centuries ago, an unknown cataclysmic event nearly tore the galaxy apart and spawned unsurmountable hyperspace rifts throughout the entire galaxy. Since then, the center of the galaxy has been cut off from the rest and a mysterious alien species, the Xsotan, has turned up there.