Masters of Orion by way of Babylon 5.
"I'd play that!" were the first words out of the mouth of my friend as I described Horizon, a space-based 4X game for PC, as being "inspired by Masters of Orion and Babylon 5." It's one of the things that separates Horizon from other 4X games, rather than the standard galaxy-conquering soft-story, Horizon's Scenario mode has story missions involving a pair of ancient races vying for domination of the galaxy.
The story missions are not obligatory; players can still play the game in "classic mode" which offers traditional storyless galaxy conquering gameplay, but without encountering the two races at the core of the story. Upon expanding into the stars, humanity encounters the Kortahz, a race of beings locked in a struggle with the Voraians.
The influence of Babylon 5 is apparent quickly, with the Kortahz ships clearly influenced by the television show's antagonists, The Shadows. In Horizon, the Voraians (who sound similar to Babylon 5's Vorlons) are an ancient race who created the Kortahz as a companion race for themselves, but they rejected their creators, making the two rivals. As the player, you get to choose with which race you wish to side with or achieve dominance in the usual 4X fashions of diplomacy, combat, and commerce.
The game's Producer/Director/Creator Raffi Parsekhian spent a lot of time developing the game's core ideas while working as an I.T. professional. Parsekhian's I.T. background has helped make the game stronger. As it's currently in beta, the opening screen has a link for reporting problems that automatically loads the appropriate saved games to the server so L3O can get a look at the issue directly and fix the bugs as fast as possible. The existing beta community, Parsekhian told me, is already very enthusiastic for the game.
The game allows you to pick the number of star systems available, has up to 80 upgradable tech types (each with ten possible upgrades), and customizable ships. Considering that you start without interstellar communication, and eventually create a galaxy-dominating empire, the potential for upgrades and expansion is vast.
In combat Horizon is turn-based ship-based combat. Ships are as customizable as everything else in the game, with different bodies, weapons, and other systems. The system of the game is not so specific that one can lost in minutiae forever, but still offers a lot of opportunities for the tinkerer.
Horizon's narrative-driven missions and turn-based, automated, but deep customization help separate it from other 4X games on the market. It is currently available in beta on Steam for PCs.