X - Space Game

X is a science fiction space trading and combat simulator series created by German developer Egosoft. The series is set in the X-Universe where several races populate a number of worlds connected by jumpgates. The games feature free roaming gameplay with trading, combat, empire building, and missions; leading to the series' phrase: "Trade, Fight, Build, Think". The series, which was launched in 1999 on the Windows platform, consists of five base games: X: Beyond the Frontier, X²: The Threat, X³: Reunion, X Rebirth, and X4: Foundations. X Rebirth introduced a new rendering engine as well as a new plot, one which X4: Foundations now extends the storyline beyond ten years after the events in X Rebirth.