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 Assault v1.3 Alpha Demo

After so many preparations and tweaks I finally bring all of you the alpha demo of the mod. Now this is an Alpha so expect bugs, glitches and other things to pop up. Now since I've got your attention the development of the mod will of course continue. Think of the alpha as a small preview that i want everyone to see how the mod actually is.

Version ComparisonMap 11Map 102012 Update2012 Update2012 Update2012 Update

Instructions how to install and play it are inside the zip file in a Readme file.

If you experience any bugs, glitches don't hesitate to let me know. I will fix any of the bugs that ya guys report (well if they are fixable ofc) it will speed up the development of the mod.


Opposing Force Assault v1 Alpha Demo

Military Duty - Mod Release

Military Duty - Mod Release

5 months ago Military Duty 14 comments

Hello people. Today I'm proud to announce you the release of a new Hl1 Opposing Force mod.

Project announcement

Project announcement

6 months ago Hl Opposing Force - Firestorm 8 comments

Today I'm announcing a smaller side project of mine. One I've been working on for quite some time now but just recently have I made massive breakthroughs...

2014 Kickoff Update

2014 Kickoff Update

1 year ago News 28 comments

The latest news on Operation Black Mesa and Guard Duty!

Half-Life: Echoes Announcement

Half-Life: Echoes Announcement

1 year ago News 27 comments

After 15 years of enjoying Half-Life, and the endless user-created content over those years, I wish to give back to the community and create my own take...

Post download RSS feed Related Downloads
Opposing Force Assault v1.3 Alpha Demo

Opposing Force Assault v1.3 Alpha Demo

3 weeks ago Opposing Force Assault Demo 4 comments

This is an Alpha demo version so the game is not complete and will be longer , expect bugs , crashes ... ect. Bug reporting is always welcomed to improve...

Opposing Force Full Installation (WinRar)

Opposing Force Full Installation (WinRar)

4 months ago Full Version 10 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

5 months ago Demo 6 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

10 months ago Mapping Tool 4 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

11 months ago Patch 4 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...



1 year ago 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...

Post comment Comments  (0 - 10 of 68)
RolandDeschain79 Sep 6 2015 says:

You can play Opposing Forces on your Android phone or tablet with Xash3D!

Half Life: Opposing Forces on Android Fixed with Xash3D (Note 2)

0 votes     reply to comment
staffssuckshit Apr 25 2015 says:

This game rocks... it brings me many of my childhood.

+2 votes     reply to comment
PunishedLamia Feb 11 2015 says:

Gearbox should release the Source Code.

+2 votes     reply to comment
hafidin Jan 25 2015 says:

how to download opposing force without mod ? please... :(

+1 vote     reply to comment
hafidin Jan 17 2015 says:

how to download ?

+2 votes     reply to comment
Dark_Assassin99 Jul 29 2014 says:

lol I love the boot camp, It's so cool.

+4 votes     reply to comment
EDOC_32 Jan 15 2014 buried:


Why Op4 is a "Game", if he is a mod for HL?, i not understand ^^

-5 votes     reply to comment
ShouldBeNew Feb 20 2014 replied:

It used to be a Half-Life mod but then Valve decided to make it a game/expansion.

-4 votes     reply to comment
Avoozl Dec 29 2013 says:

It doesn't make sense how they replaced the SMG MP5 with a AR M4 in the Hi-Res update pack.

+2 votes     reply to comment
alencore Aug 1 2015 replied:

You can put whatever weapon you want in Op4, I prefer an AK74.

+1 vote     reply to comment
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Half-Life: Opposing Force
Gearbox Software
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Released 1999
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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

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