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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Opposing Force Boot Camp and We Are Pulling Out Boot Camp and We Are Pulling Out
Blog RSS Feed Report abuse Latest News: 2014 Kickoff Update

15 comments by Uphys on Mar 29th, 2014

Welcome to our first media update this year!

Read Full Article.

Multiplayer Beta Release Q1 2014 Cancelled

Our plan to bring you the multiplayer beta of Operation Black Mesa early this year didn't work out, regrettably. Several factors and circumstances forced us to completely keep it under the hood until further notice.

Multiplayer Progress

Multiplayer will feature classic maps such as Yard, Crossfire and Boot Camp as well as brand-new ones like Deptcharge and Gambit from day 1.
Currently in development: CTF mode and weapon placement.


Singleplayer Campaign

Development is running smoothly; those NPCs aren't going to animate themselves though! If you're interested in joining our team, check out the jobs page where you can find all positions currently open. We look forward to welcoming you on board!

Pit Worm's Nest

Remember Guard Duty (Blue Shift: Source)? We're making solid progress here too:

Living Quarters Outbound

OBM: The Video Game?

We've been given the option of developing our projects as full indie titles to be sold on Steam!
This opens up a whole lot of attractive possibilities to consider; however no decision has been reached yet as to this matter.

Alien Controller

M1A1 Tank

Thanks for your support in making all of this possible!

Until next time,
Tripmine Dev Team

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Apr 1, 2014 Half-Life Patch 2 comments

This is Further-Data, a small bonus CD released for free in 1999 via retail channels to Half-Life players. It contains bonus audio and music, lots of...

Shepard's Adventures
Half-Life: Opposing Force

Shepard's Adventures

Mar 31, 2013 Shepard's Adventures Full Version 0 comments

Hello everybody! Here is my old single player map pack for Opposing Force. This mappack is more of the demo to my unfinished full-scale modification...

Botman's Bots (HPB-BOT) 4.0

Botman's Bots (HPB-BOT) 4.0

Jan 22, 2013 Half-Life Other 2 comments

HPB BOT only for the following mods:Opposing Force,Deathmatch Classic,Team Fortress 1.5,Ricochet and of course Half-Life Only for WON versions Metamod...

Half-Life: Opposing Force


Aug 1, 2012 Retaliation Full Version 2 comments

“Retaliation picks up where Dark Operations left off. There will be no Xen or displacer in Retaliation. Action is the main theme. It will mainly be an...

Dark Operations
Half-Life: Opposing Force

Dark Operations

Aug 1, 2012 Dark Operations Full Version 1 comment

“It has several puzzles to make it more thinking oriented as well as being full of action. You will traverse and do battle in many different places: labs...

Little Sky Scraper of Horrors
Half-Life: Opposing Force

Little Sky Scraper of Horrors

Aug 1, 2012 Little Sky Scraper of Horrors Full Version 0 comments

The Bad Guys have taken over a building in a Generic American City, and they’ve kidnapped some Innocent Scientists and forced them to genetically engineer...

Post comment Comments  (40 - 50 of 66)
Riker7 Mar 26 2010, 3:14pm says:

i have the Jed's Half-Life Model Viewer 1.36
and ai saw the blackops osprey
in the game i cant see it ...

+1 vote     reply to comment
Headshot_ Feb 12 2010, 5:21pm says:

I think its a good addon and I real like the training :D

+2 votes     reply to comment
REENIGAV Nov 27 2009, 2:11pm says:

half life opposing force is one of the best half life

+4 votes     reply to comment
callea Oct 31 2009, 7:52am says:

Why dont ANYONE make a port of it? to the orangebox engie? like Heart of evil source.

-2 votes     reply to comment
InSovietRussia Mar 9 2010, 9:04pm replied:

operation black mesa, coming eventually.

+2 votes     reply to comment
m82sniper Nov 18 2009, 2:33pm replied:

There are people re-making it on the Source engine, but a straight out port is just retarded.

+3 votes     reply to comment
InSovietRussia Jul 17 2010, 6:59am replied:

Go buy it on steam.

+1 vote     reply to comment
InSovietRussia Mar 9 2010, 9:06pm replied:

yep opposing force, blue shift, counterstrike, day of defeat, ricochet, are all mods of half-life. even if you can buy cs or dod on steam without half life, they are mods of half life because they run off of hl.exe

+1 vote     reply to comment
Thanoshld Feb 6 2010, 3:19pm replied:

An expansion to be correct.Along with Blue Shift.

+2 votes     reply to comment
AlekZanDer Sep 24 2009, 3:22pm replied:

Are you surprised?Than why do you think it has HL graphics,monsters and textures?

+2 votes     reply to comment
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Half-Life: Opposing Force
Gearbox Software
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Release Date
Released Oct 30, 1999
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232 votes submitted.

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Highest Rated (4 agree) 10/10

The campaign is almost as good as HL's but the multiplayer is just the icing on the cake, Oh but the the cake is lie... oh well.

Nov 21 2010, 10:17am by X-LAyer2

First Person Shooter
Single Player
Expansion Pack
This game is an expansion for Half-Life
More Expansions
Half-Life: Decay, Released Nov 14, 2001
Half-Life: Blue Shift, Released Jun 11, 2001
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