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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About Military Duty with 14 comments by 23-down on Jun 28th, 2015

Howdy folks. Today I'm proud to announce you the release of a new Half-Life: Opposing Force mod (Op4 not required) It is a map pack that consists of 15 maps in decent quality. The mod features custom skins, few new voice lines as well as rather balanced game play. There're still few minor glitches in it which eventually may get addressed in a future patch but nothing serious. The mod is completely playable.

Military Duty

Story wise the map pack plays during the events of the official Hl1 games , Op4, Blue Shift, Decay & the original Hl with Freeman. So nothing fancy here.

Anyway for those unfamiliar with this project so far. Let me introduce it a little bit for you. This mod has been a little side project of mine that I started several years ago but just recently I finally managed to return for it and to finish it. Keep in mind though that this is my first mod release ever for Half-Life. So I'm hoping for many comments from you people either here or on the site that hosts my mod. Positive feedback as well as constructive criticism would be most appreciated.

Special thanks go to all of you my followers and my team mates which helped me on this package as well as my beta testers and everyone else who was somehow involved on this project. But enough talking. I'm sure each one of you would like to play it now.

Important: In it|s current state the mod is not fully compatible with the old WON version of Half-Life. Please keep that in mind. I suggest playing it on steam only.

So here you go:

Download here

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Opposing Force Full Installation

Opposing Force Full Installation

Jul 25, 2015 Full Version 8 comments

This is Opfor Installation. Which is a full version 1.2. And it includes also the Capture the flag for those who want.This also includes the map from...

Opposing Force: Source

Opposing Force: Source

Jun 12, 2015 Demo 5 comments

Ok before i say anything about this i need to say this: AW HECK YA ITS OUT!!! Its not out its just what i made so far OH that reminds me sense this is...

Half-Life: Opposing Force FGD for Jackhammer

Half-Life: Opposing Force FGD for Jackhammer

Jan 3, 2015 Mapping Tool 2 comments

This FGD file modified for the Half-Life: Opposing Force enables the visualization of models (weapons, enemies, items ...) in Jackhammer editing screen...

Half-Life: Opposing Force SP Map fixes patch

Half-Life: Opposing Force SP Map fixes patch

Dec 14, 2014 Patch 3 comments

Contains bug fixes for various map for Half-Life: Opposing Force - single player. To note that the structure of the maps isn't changed at all , only entities...



Oct 21, 2014 Improvement weapons models Full Version 0 comments

Full version. Improvement weapons models for Opposing Force. Full version. Improvement weapons models for Opposing Force. Full version. Improvement weapons...

Sledge Alpha Build

Sledge Alpha Build

Aug 19, 2014 Mapping Tool 5 comments

Sledge is a completely free and open-source replacement for Valve's Hammer Editor, with a focus on compatibility with both Goldsource and Source engines...

Post comment Comments  (20 - 30 of 68)
E3Pointman Apr 18 2011 says:

I love this Game , i just love it!!!!Ahhh good memories :P

+2 votes     reply to comment
AmaroqDricaldari Apr 10 2011 says:

I want someone to make the LongJump Module useable in Half-Life 2, GMod, and Half-LIfe Opposing Force. I am starting to get annoyed that nobody has done that yet.

+1 vote     reply to comment
notasinglenamedperso Oct 29 2011 replied:

They cannot do it for HL2 or Gmod because that is on the source engine and that would be porting and if they did port it it would be illegal and it wouldn't work. For opposing force you do not need to download anyhting just when your in the main menu open the console and type "sv-cheats 1" without the quotes and load a level and then open the console again and type "give item_longjump" without the quotes. it will automaticaly give you hl1's longjump and you can use it.

-1 votes     reply to comment
RangerC Mar 19 2011 says:

OP4 + Joebama's server = maximum WIN

+4 votes     reply to comment
sasasa Dec 27 2010 says:

anyone interested in making new/ high quality drill instructor, 9mm, 9mmAR,.. And all of the others?
don't mention about the redux
oh, and HD map textures???

+1 vote     reply to comment
JrComissarValvatorez Dec 30 2010 replied:

Right now I'm just crossing my fingers and hoping Opposing Force is the next thing Richard does after Half Life for his Ultra definition packs.

+1 vote     reply to comment
JrComissarValvatorez Nov 10 2010 says:

Some up to date models packs would be most appreciated, I haven't been able to find decent replacements for the M249 Saw and the Sniper Rifle and am now using conversions from CS:S with crappy low resolution textures.

+1 vote     reply to comment
JrComissarValvatorez Nov 13 2010 replied:

Found a decent M249 converted from Condition Zero even though it's compiled for Sven Coop, still looking around for a decent M24 for sniper rifle though.

+1 vote     reply to comment
[OTC]SMOKEY Nov 9 2010 says:

As long as u dont scrap the project, I dont really feel betrayed. Meaning that this and any other op4 mods progress, for me, is anxiously anticipated. Thanks for the update

+1 vote     reply to comment
$$$killer$$$ Oct 19 2010 says:

buy hl from 9,99 dollars and opposing force 4,99 dollars

+1 vote     reply to comment
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Half-Life: Opposing Force
Gearbox Software
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Release Date
Released Oct 1999
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242 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 by X-LAyer2

First Person Shooter
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Half-Life: Decay
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