X-Tension is the eagerly awaited expansion pack to X: Beyond the Frontier. The expansion is not limited by a linear plot line but makes use of new ways to expand your empire. You can now take part in missions that are offered to you throughout the game. 

X: Beyond The Frontier is the first part in the X-Universe series of games developed by Egosoft. It tells the story of mankind's rise and fall in the universe, and the attempt by Kyle Brennan to help repopulate the stars using a new ship called the Experimental Shuttle, and how he became trapped in a closed group of sectors linked by a series of jumpgates, owing credits to an alien for helping to save him, and hunted by several people. Unknowingly, a group of secret service people are after him, a group who have tried to hide their races secret, that they are the descendants of a group of Humans who saved earth from the Terraformer fleet they created to help colonise the universe. 

X²: The Threat is of a new generation of space simulator games, you play the role of Julian Gardna who continues the story set by X: Beyond The Frontier. The updated graphics engine gives the universe a fresher feel with newly designed ships and stations adding to the complexity of the universe. 

The Sequel to the award winning X²: The Threat introduces a new 3D engine as well as a new story, new ships and a new gameplay to greatly increase the variety in the X-universe. The economy of X³: Reunion is more complex than anything seen in the X-universe before. Factories are being built by NPCs, wars can affect the global economy, NPCs can trade freely and pirates behave far more realistically.