Half-Life: Opposing Force is an expansion pack for Valve Software's science fiction first-person shooter video game Half-Life. The game was developed by Gearbox Software and published by Sierra Entertainment on November 1, 1999. Opposing Force is the first expansion for Half-Life and was first announced in April 1999. Randy Pitchford, the lead designer on the game, later noted that he believed Gearbox was selected to develop Opposing Force because Valve wanted to concentrate on their future projects. Over the course of development, Gearbox brought in a variety of outside talent from other areas of the video games industry to help bolster various aspects of design. Opposing Force returns to the same setting as Half-Life, but instead portrays the events from the perspective of a U.S. Marine, one of the enemy characters in the original game. The player character, Adrian Shephard.

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Good expansion pack

One of the best Expansion Packs out there for any PC Game!

A great expansion to an awesome game.

No Half-Life or FPS player would hate this mod! Awesome gameplay, a satisfying arsenal of weapons, the enemies... AND SO MUCH MORE!!! HL:OF rocks! \m/


Half-Life:Opposing Force comes from an era that expansion packs still mattered. If you loved the original game, this one will make you think that maybe it is even better than Half-Life itself.

8 ball from gta advance

Best half life official mod

Someone at Gearbox must really like Starship Troopers and the Alien films.

A strange yet interesting direction for the events of Black Mesa from the point of view of a young marine jarhead, who is a member of the same special operations battalion sent in to clean up the facility, and kill a certain pesky mute MIT graduate from the original Half-Life.

His journey through the base won't be easy as he has to deal with a bunch of new enemies, like Having to face off with a bunch of ****** off space cockroaches, A group of military specialists who love the color black, and one sneaky inter dimensional bureaucrat.

This expansion doesn't have the best plot, but it will keep you playing with the expansion's new gameplay mechanics such as the rather neat Barnacle Grapple, the incredibly cute Spore Launcher <3. Oh and Otis the lovable oaf.

Overall, a really great taste of Half-Life content!

One of the best games I've ever played!


The best official expansion pack for Half-Life.

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Highest Rated (3 agree) 10/10

One of the best Expansion Packs out there for any PC Game!

Jan 15 2018 by SweetTigress