Gearbox Software's 1999 classic — its history, how the press received it, how it plays today, and what a copy costs.
- Released
- 1999 · PC (DOS / Windows)
- Developer
- Gearbox Software
- Publisher
- Sierra On-Line
- MobyScore
- ★ 8.04
- Players today
- Overwhelmingly Positive on Steam (95% of 15600)
The history
Released in 1999, Half-Life: Opposing Force serves as the first official expansion to the landmark title Half-Life. Developed by Gearbox Software under the supervision of Valve, the project aimed to expand the universe of the Black Mesa Research Facility by introducing a new perspective on the catalyst event.
The game mattered by shifting the narrative lens to Corporal Adrian Shephard, a military specialist sent to "clean up" the incident and silence witnesses. By interweaving its story with the base game, it allowed players to witness the same events as Gordon Freeman from a different angle, while establishing a new standard of quality for action-game mission packs.
How it plays
The gameplay loop follows Shephard's struggle for survival after his helicopter is shot down and his squad is killed. Players navigate 12 interconnected levels, utilizing a mix of new weaponry and combat tactics to fight fierce alien opponents such as Pit Drones, Voltigores, Shock Troopers, and Zombie Grunts.
A key mechanical addition is the ability to command AI-controlled teammates. Players can call upon standard grunts and heavy gunners for support fire, utilize engineers to cut through doors, or rely on medics to restore health, with some areas requiring squadmate assistance to complete.
How it was received
Opposing Force was received with general acclaim, earning a 85.45% score on GameRankings. High marks came from GamePro (5/5), CVG (9/10), and GSpot (9/10), while other outlets like GameFan (85/100), PCZone (85%), and IGN (7.5/10) were also positive. It sold 108,008 copies in the US by the end of 1999 and eventually surpassed 1.1 million copies at retail. The game was named "Computer Action Game of the Year" by the Academy of Interactive Arts and Sciences and "Best Expansion Pack" by PC Gamer US.
Critics generally praised the design; GameSpot's Erik Wolpaw called it an "impassioned application of creative design," and CVG's Kim Randell described it as an "awesome achievement." However, some dissent existed, with PC Zone calling it "pedestrian Half-Life padding" and Eurogamer noting that the developers seemed to run out of time toward the end. Today, the game maintains an "Overwhelmingly Positive" sentiment on Steam, suggesting a lasting appeal that matches its initial critical success.
In the magazines
The period press.
CVG gave the game a 9/10, and GamePro awarded it a perfect 5/5. PC Zone provided an 85% score, and GameFan rated it 85/100.
What players say today
Modern players on Steam overwhelmingly praise the game, with 14,856 out of 15,600 reviews being positive. Some users describe it as "super duper fun" and a great package of the best bits of the original. However, a few players find it difficult on normal settings or feel that the game has not aged well, recommending it primarily for its lore and contemporary significance.
“Opposing Force takes the best bits of the original Half-Life and mixes them into a small package. Think of it as just more Half-Life. You play through the Black Mesa incident from a new perspective, e…”
“very good game but a little bit hard but just a little bit its a good game.”
“I can't say that this game has aged well at all, the recommendation is solely because of lore and contemporary reasons. I also found it very difficult on normal”
Screenshots
The box & the art
Cover art, and real copies photographed in the wild.
Legacy
Gearbox Software's work on the expansion solidified their early reputation for high-quality action design. Half-Life: Opposing Force remains worth seeking out today for those who want to experience the Black Mesa incident from a fresh perspective and utilize the unique squad-command mechanics.
What it's worth
A second-hand market that moves over time — a loose disc is pocket-money, while sealed or complete-with-manual copies drive the top end. For today's exact listings, check the live search.
See current copies on eBay →Copies in the wild
Real listing photos — the range of condition you'll meet.
Photographed examples from past listings — illustrative of condition, not a live inventory.
How to play it in 2026
Easiest today: Steam or GOG (DRM-free) on modern Windows. Either way the core game is intact.
The Steam version of the game is standalone.
Verdict
Opposing Force holds up as a tight, focused expansion that successfully iterates on the Half-Life formula. By introducing new enemies and a squad system, it provides a distinct flavor of action that differentiates it from the base game.
While some modern players may find the difficulty spikes or aging graphics a hurdle, its status as a "continuation of a masterpiece" remains intact. It is a concise, high-energy trip back to one of gaming's most iconic settings.
Sources: MobyGames, Steam, and period/web coverage. Prices reflect the second-hand market and change over time.