Ludography
80/100
Players408 ratings
70/100
Critics1 review
More scores
Metacritic usersuser score
85/100
GameFAQsJust Right
3.88/5
Player reviews
95% positive25,682 reviews
Steam Deck
Playable
Runs on
Windows, Mac, Linux
Price
US$4.99

Where to get it

Half-Life: Opposing Force cover

1999 · Standalone expansion · Gearbox Software · First-person shooter · Platformer

Half-Life: Opposing Force

Standalone expansion

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, is sent in to neutralize the Black Mesa Research Facility after a scientific mishap causes it to be invaded by aliens, but quickly finds that the Marines are outnumbered and slowly being beaten back by a second alien race and black operations units.

Also known as
HL: Opposing Force · HL:OF · hl.exe · OP4 · OPFOR · HL: OPFOR · HL: OP4
Released
19 November 1999
Platforms
WindowsLinuxmacOS
Genres
First-person shooterPlatformerPuzzleScienceShooter
Developers
Gearbox Software
Publishers
—
Modes
MultiplayerSingle-player
Perspective
First person
Themes
ActionScience fictionThrillerWarfare
Engine
GoldSrc
Country
United States
Age ratings
PEGI 16ESRB M
Languages
EnglishFrenchGermanKorean
Time to beat
4.5hmain story6hwith extras5.5hcompletionist
Composers
Ben Houge

About

Half-Life: Opposing Force is an expansion pack for the first-person shooter game Half-Life (1998). It was developed by Gearbox Software and published by Sierra On-Line for Windows on November 19, 1999. Opposing Force was the first expansion for Half-Life and was announced in April 1999. Lead designer Randy Pitchford believed Gearbox was selected to develop Opposing Force because Valve, the creators of Half-Life, wanted to concentrate on their future projects. Over the course of development, Gearbox brought in a variety of talent from other areas of the video games industry to help bolster various aspects of design.

Opposing Force portrays the events of Half-Life from the perspective of a U.S. Marine, one of the enemy characters in the original, assigned to the Hazardous Environment Combat Unit (HECU). The player character, Adrian Shephard, is sent in to neutralize the Black Mesa Research Facility when a scientific mishap causes it to be invaded by aliens, but quickly finds that the Marines are outnumbered and slowly being beaten back by a second alien race and black operations units.

›Story

Opposing Force opens with Shephard riding on a V-22 Osprey with his squad. His squad discuss their deployment, somewhat irritated that they have not been told what they are being deployed for. However, as they are nearing their Landing Zone at Black Mesa, airborne alien creatures attack the Osprey formation, causing Shephard's Osprey to crash land. Shephard regains consciousness in a Black Mesa medical bay, tended to by the science team, learning that the Marines are being steadily beaten by the alien forces from Xen and orders have come through to pull out.

Consequently, Shephard departs to reach an extraction point and escape the facility. However, Shephard is prevented from reaching the extraction point by the enigmatic G-Man, forcing the evacuation craft to leave without him.

Other Marines who have also been left behind team up with Shephard and attempt to reach another extraction point near Black Mesa's Lambda Complex, but en route they come under attack from black operations units seeking to thoroughly contain the situation and eliminate all survivors. Shephard makes it to the Lambda Complex alive, and briefly sees Gordon Freeman as the latter teleports to Xen in the final stages of Half-Life. To escape the teleportation chamber, Shephard is forced to enter a separate portal, briefly taking him to Xen before depositing him in an entirely different area of the facility. The facility is now heavily damaged, and it soon becomes clear that a new alien race, Race X, has exploited the situation to mount a localized invasion, attacking both human and Xen forces in Black Mesa indiscriminately. Fighting between the black operations units and Race X quickly intensifies.

Shephard soon encounters more stranded Marine units in the wreckage of the base, and tries to break through the black operations units to reach an escape point past the facility's storage unit, but meets heavy resistance from both Race X and the black operations units. A surviving Black Mesa security guard reveals to Shephard that the black operators intend to detonate a tactical nuclear weapon in the base, thereby totally sealing it off and killing everything in it. After successfully neutralizing the guarding black operations unit, Shephard disarms the device and proceeds to the nearby storage areas, intent on escape. However, the G-Man rearms the device as Shephard departs. The storage unit has become a thick battleground between Race X and the black operation units, and although Shephard manages to evade them, he is informed by another security guard that something very large is coming through an alien portal blocking the exit path.

At the portal, Shephard discovers a gene worm, a massive creature facilitating the Race X invasion. Shephard is able to kill the creature, but just afterwards he is teleported onto an Osprey by the G-Man. As the G-Man congratulates Shephard on his accomplishments, the nuclear device detonates in the background, destroying Black Mesa. The game closes with the G-Man detaining Shephard someplace where he can tell no one of what he has seen and cannot be harmed, pending further evaluation.

Players say

Media

The articlegameplay, story, development, reception

Gameplay

As an expansion pack for Half-Life, Opposing Force is a first-person shooter. The overall gameplay of Opposing Force does not significantly differ from that of Half-Life. Players navigate through levels, fight hostile non-player characters and solve a variety of puzzles to advance. The game continues Half-Life's methods of an unbroken narrative.

The player sees everything through the first person perspective of the protagonist and remains in control of the player character for almost all of the game. Story events are conveyed through the use of scripted sequences rather than cut scenes. Progress through the world is continuous; although the game is divided up into chapters, the only significant pauses are when the game needs to load the next part of an environment. Opposing Force also features an extended multiplayer, incorporating the various new environments and weapons into the original deathmatch mode used in Half-Life.

Story

Opposing Force builds on the setting and events of Half-Life, taking place at a remote New Mexico laboratory called the Black Mesa Research Facility. In Half-Life, the player takes on the role of Gordon Freeman, a scientist involved in an accident that opens an interdimensional portal to the borderworld of Xen, allowing the alien creatures of Xen to attack the facility. The player controls Freeman in an attempt to escape the facility and close the portal, ultimately traveling to Xen to do so. Opposing Force, however, shows the events of Half-Life from the perspective of a different protagonist.

S. Marine Corps Corporal assigned to the Hazardous Environment Combat Unit, a specialized unit sent in to Black Mesa by the government to quell the alien threat and silence all witnesses. However, after Shephard becomes isolated from his fellow Marines, he must ally with the Black Mesa personnel and attempt to escape the base.

Development

Half-Life: Opposing Force was announced by developer Gearbox Software on April 15, 1999. In their press release, founder Randy Pitchford stated that "our number one goal is to preserve the integrity of Half-Life and provide new experiences that expand upon the sensation of the original". The name Opposing Force has a double meaning, referring both to the fact that the player is one of the enemies in the original game, as well as to Newton's third law of motion. In a later interview, Pitchford stated that he believed that Valve offered Gearbox the chance to make a Half-Life expansion was from a wish "to focus on their future titles".

In addition, Pitchford commented that Valve and Gearbox had agreed not to "severely modify" the game engine used by Half-Life and Opposing Force as it "risks breaking all of the wonderful work" that the game's custom content community was creating. Substantial information on Opposing Force's development direction, as well as new locations, characters and story were revealed at the 1999 Electronic Entertainment Expo convention. The official website for Opposing Force, hosted by publisher Sierra Studios, was put online in July 1999. Opposing Force was developed in 8 months by a team of more than 15 people.

Reception

Opposing Force received mainly positive reviews, holding a score of 85.45% on the review aggregator site GameRankings. In the United States, the game sold 108,008 copies by the end of 1999. Although figures for sales on Steam have not been released, Opposing Force eventually sold over 1.1 million copies at retail.

Computer and Video Games reviewer Kim Randell noted that "Gearbox has obviously gone to great pains to provide a similar experience to the original". Praise was also given to the multiplayer; Randell stated that the new additions for multiplayer made it the area of Opposing Force that "really shines". Randell closed the review by concluding that Opposing Force is "an awesome achievement". Erik Wolpaw, writing for GameSpot, noted that as most expansion packs were mediocre, "it's appropriate that Gearbox Software's Opposing Force, the official expansion for the genre-redefining Half-Life, in turn sets a new standard of quality for future action-game mission packs".

Releases by platformdates and regions as published

Releases by platform
PlatformReleasedRegions
Windows10 November 1999North America · Europe 15 November 1999
Linux31 July 2013Worldwide
macOS31 July 2013Worldwide

Decompilations and portscommunity projects that rebuild or port the game

Editions and related releases

Included in
Valve Complete PackHalf-Life: GenerationHalf-Life 1 Anthology
Follows
Half-Life
Part of
Half-Life
Built on it
Nuclear Winter
Standalone expansion of
Half-Life

Games like this

Collections1 collection

Description adapted from its source, CC BY-SA 4.0.