Halo: Combat Evolved

Nov 15, 2001ShooterXboxPC (Microsoft Windows)MacXbox 360 Xbox One

About Halo: Combat Evolved

Bent on Humankind's extermination, a powerful fellowship of alien races known as the Covenant is wiping out Earth's fledgling interstellar empire. Climb into the boots of Master Chief, a biologically altered super-soldier, as you and the other surviving defenders of a devastated colony-world make a desperate attempt to lure the alien fleet away from earth. Shot down and marooned on the ancient ring-world Halo, you begin a guerilla-war against the Covenant. Fight for humanity against an alien onslaught as you race to uncover the mysteries of Halo.

Summary via IGDB.

Halo: Combat Evolved on Wikipedia

Halo: Combat Evolved is a 2001 first-person shooter game developed by Bungie and published by Microsoft Game Studios. The game was released on November 15, 2001 for the Xbox, with ports to Microsoft Windows and Mac OS X released in 2003. It is the first installment in the Halo franchise. Set in the 26th century, players assume the role of Master Chief, a cybernetically enhanced supersoldier. Accompanied by an artificial intelligence construct named Cortana and the forces of the United Nations Space Command (UNSC), players battle against an alien theocracy known as the Covenant while they attempt to uncover the secrets of the eponymous Halo, a ring-shaped artificial world.

Source: Wikipedia (text under CC BY-SA 4.0).