Half-Life: Opposing Force is the official game expansion for Half-Life, the thrilling PC CD-ROM named "Game of the Year" by over 50 publications. In Opposing Force (a.k.a. "Op For"), players return to the Black Mesa Research Facility to experience an entirely new episode of single player action. In addition, Op For also contains a massive collection of new multiplayer content.

The Story

Remember the soldiers who gave you so much trouble in Half-Life? Now you are one of them--and life is not so easy as part of the Opposing Force.

As a soldier sent in to eliminate Gordon Freeman, you are separated from your base unit and discover a new alien race amidst the chaos. It's quickly revealed that these highly advanced alien life forms descended upon Earth to pillage the planet from the Black Mesa facility when Gordon Freeman transported to the border world of Xen.

Although you were originally sent into Black Mesa to silence Freeman and his fellow scientists in the facility, you now find yourself stranded and confused--battling fierce new alien creatures and a variety of other foes in an effort to save your own life.

But as a military specialist, you are not unarmed. You'll gather a custom arsenal of new military firearms, experimental weapons and deadly alien devices. And, as you explore further areas of Black Mesa, you will encounter a new variety of human characters to interact with--on both friendly and unfriendly terms.

In addition to the extensive new single player experience, Opposing Force will also contain a robust collection of fresh multiplayer content, including new weapons, player characters (models), and several new multiplayer maps designed by the experts at Gearbox Software. Opposing Force will also feature new levels created by all-star legends of the Dallas gaming community.

Opposing Force is being developed by Gearbox Software and published by Sierra. This official game extension is due to arrive in retail stores everywhere this November.

Key Features
  • Return to the Black Mesa Research Facility as a soldier.
  • Experiment with a host of new military, experimental and alien weapons.
  • Battle a fierce new alien race and interact with more human characters.
  • Compete in new multiplayer maps designed by industry all-stars.

Opposing Force Introduction provided by Sierra's Official Opposing Force.