The Game Census
Half-Life: Opposing Force cover art

Half-Life: Opposing Force

Gearbox Software · Valve · 1999-11-01

Steam

Action

Franchise: Half-Life · Modes: Single player, Multiplayer

Releases: Nov 10, 1999 (PC (Microsoft Windows)), Jul 31, 2013 (Linux), Jul 31, 2013 (Mac)

Return to the Black Mesa Research Facility as one of the military specialists assigned to eliminate Gordon Freeman. Experience an entirely new episode of single player action. Meet fierce alien opponents, and experiment with new weaponry. Named 'Game of the Year' by the Academy of Interactive Arts and Sciences.

100
playing now
95%
positive of 29k reviews
Overwhelmingly Positive
steam rating
2,000,000–5,000,000
owners (SteamSpy est.)
70/100
critic score (1 outlets, IGDB)
80/100
IGDB user rating (399 ratings)
6.1h
to beat · rushed 4.3h · completionist 5.3h
platinum
deck/linux tier (ProtonDB)
$4.99
steam price (US)

100 players in-game as of 2026-08-30 01:00 UTC (census sample)

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.

Health check

Healthy
  • · 100 players in-game at the last census sample.
  • · 2,397 reviews in the last 8 weeks (~300/week).
  • · Review velocity up 29% vs the prior 8 weeks.
  • · Top 6% of 10,791 Action games in the census by review count.

Health tier since 2026-08-30

Estimated sales: 1.2M–2.3M copies

Review-multiple estimate from 28,897 total reviews — how this is computed.

All-time low: $0.49 at Steam (2019-06-26)via IsThereAnyDeal

12-month high $4.99 · on sale 4 of 8 observed days (census price snapshots)

Review momentum

PositiveNegative
59759720182026Week of 2018-01-01: 87 positiveWeek of 2018-01-01: 8 negativeWeek of 2018-02-01: 72 positiveWeek of 2018-02-01: 5 negativeWeek of 2018-03-01: 65 positiveWeek of 2018-03-01: 5 negativeWeek of 2018-04-01: 50 positiveWeek of 2018-04-01: 6 negativeWeek of 2018-05-01: 53 positiveWeek of 2018-05-01: 4 negativeWeek of 2018-06-01: 90 positiveWeek of 2018-06-01: 3 negativeWeek of 2018-07-01: 104 positiveWeek of 2018-07-01: 11 negativeWeek of 2018-08-01: 50 positiveWeek of 2018-08-01: 3 negativeWeek of 2018-09-01: 59 positiveWeek of 2018-09-01: 2 negativeWeek of 2018-10-01: 38 positiveWeek of 2018-10-01: 3 negativeWeek of 2018-11-01: 86 positiveWeek of 2018-11-01: 4 negativeWeek of 2018-12-01: 59 positiveWeek of 2018-12-01: 3 negativeWeek of 2019-01-01: 83 positiveWeek of 2019-01-01: 5 negativeWeek of 2019-02-01: 67 positiveWeek of 2019-02-01: 1 negativeWeek of 2019-03-01: 41 positiveWeek of 2019-03-01: 4 negativeWeek of 2019-04-01: 44 positiveWeek of 2019-04-01: 7 negativeWeek of 2019-05-01: 36 positiveWeek of 2019-05-01: 5 negativeWeek of 2019-06-01: 158 positiveWeek of 2019-06-01: 5 negativeWeek of 2019-07-01: 200 positiveWeek of 2019-07-01: 11 negativeWeek of 2019-08-01: 64 positiveWeek of 2019-08-01: 7 negativeWeek of 2019-09-01: 53 positiveWeek of 2019-09-01: 6 negativeWeek of 2019-10-01: 71 positiveWeek of 2019-10-01: 5 negativeWeek of 2019-11-01: 198 positiveWeek of 2019-11-01: 5 negativeWeek of 2019-12-01: 320 positiveWeek of 2019-12-01: 19 negativeWeek of 2020-01-01: 261 positiveWeek of 2020-01-01: 11 negativeWeek of 2020-02-01: 159 positiveWeek of 2020-02-01: 7 negativeWeek of 2020-03-01: 229 positiveWeek of 2020-03-01: 8 negativeWeek of 2020-04-01: 314 positiveWeek of 2020-04-01: 14 negativeWeek of 2020-05-01: 200 positiveWeek of 2020-05-01: 7 negativeWeek of 2020-06-01: 195 positiveWeek of 2020-06-01: 5 negativeWeek of 2020-07-01: 314 positiveWeek of 2020-07-01: 11 negativeWeek of 2020-08-01: 206 positiveWeek of 2020-08-01: 9 negativeWeek of 2020-09-01: 160 positiveWeek of 2020-09-01: 5 negativeWeek of 2020-10-01: 177 positiveWeek of 2020-10-01: 4 negativeWeek of 2020-11-01: 222 positiveWeek of 2020-11-01: 9 negativeWeek of 2020-12-01: 340 positiveWeek of 2020-12-01: 17 negativeWeek of 2021-01-01: 371 positiveWeek of 2021-01-01: 21 negativeWeek of 2021-02-01: 255 positiveWeek of 2021-02-01: 15 negativeWeek of 2021-03-01: 222 positiveWeek of 2021-03-01: 7 negativeWeek of 2021-04-01: 202 positiveWeek of 2021-04-01: 12 negativeWeek of 2021-05-01: 219 positiveWeek of 2021-05-01: 6 negativeWeek of 2021-06-01: 224 positiveWeek of 2021-06-01: 21 negativeWeek of 2021-07-01: 421 positiveWeek of 2021-07-01: 15 negativeWeek of 2021-08-01: 258 positiveWeek of 2021-08-01: 9 negativeWeek of 2021-09-01: 208 positiveWeek of 2021-09-01: 13 negativeWeek of 2021-10-01: 183 positiveWeek of 2021-10-01: 9 negativeWeek of 2021-11-01: 210 positiveWeek of 2021-11-01: 17 negativeWeek of 2021-12-01: 303 positiveWeek of 2021-12-01: 11 negativeWeek of 2022-01-01: 328 positiveWeek of 2022-01-01: 18 negativeWeek of 2022-02-01: 270 positiveWeek of 2022-02-01: 10 negativeWeek of 2022-03-01: 213 positiveWeek of 2022-03-01: 10 negativeWeek of 2022-04-01: 153 positiveWeek of 2022-04-01: 8 negativeWeek of 2022-05-01: 161 positiveWeek of 2022-05-01: 9 negativeWeek of 2022-06-01: 188 positiveWeek of 2022-06-01: 15 negativeWeek of 2022-07-01: 377 positiveWeek of 2022-07-01: 24 negativeWeek of 2022-08-01: 247 positiveWeek of 2022-08-01: 11 negativeWeek of 2022-09-01: 164 positiveWeek of 2022-09-01: 12 negativeWeek of 2022-10-01: 127 positiveWeek of 2022-10-01: 10 negativeWeek of 2022-11-01: 248 positiveWeek of 2022-11-01: 15 negativeWeek of 2022-12-01: 407 positiveWeek of 2022-12-01: 34 negativeWeek of 2023-01-01: 431 positiveWeek of 2023-01-01: 30 negativeWeek of 2023-02-01: 245 positiveWeek of 2023-02-01: 11 negativeWeek of 2023-03-01: 325 positiveWeek of 2023-03-01: 19 negativeWeek of 2023-04-01: 277 positiveWeek of 2023-04-01: 17 negativeWeek of 2023-05-01: 245 positiveWeek of 2023-05-01: 10 negativeWeek of 2023-06-01: 224 positiveWeek of 2023-06-01: 13 negativeWeek of 2023-07-01: 440 positiveWeek of 2023-07-01: 25 negativeWeek of 2023-08-01: 442 positiveWeek of 2023-08-01: 20 negativeWeek of 2023-09-01: 304 positiveWeek of 2023-09-01: 10 negativeWeek of 2023-10-01: 217 positiveWeek of 2023-10-01: 18 negativeWeek of 2023-11-01: 559 positiveWeek of 2023-11-01: 33 negativeWeek of 2023-12-01: 597 positiveWeek of 2023-12-01: 44 negativeWeek of 2024-01-01: 442 positiveWeek of 2024-01-01: 31 negativeWeek of 2024-02-01: 260 positiveWeek of 2024-02-01: 19 negativeWeek of 2024-03-01: 367 positiveWeek of 2024-03-01: 26 negativeWeek of 2024-04-01: 284 positiveWeek of 2024-04-01: 19 negativeWeek of 2024-05-01: 256 positiveWeek of 2024-05-01: 14 negativeWeek of 2024-06-01: 262 positiveWeek of 2024-06-01: 27 negativeWeek of 2024-07-01: 401 positiveWeek of 2024-07-01: 19 negativeWeek of 2024-08-01: 298 positiveWeek of 2024-08-01: 14 negativeWeek of 2024-09-01: 232 positiveWeek of 2024-09-01: 14 negativeWeek of 2024-10-01: 175 positiveWeek of 2024-10-01: 10 negativeWeek of 2024-11-01: 474 positiveWeek of 2024-11-01: 22 negativeWeek of 2024-12-01: 510 positiveWeek of 2024-12-01: 28 negativeWeek of 2025-01-01: 375 positiveWeek of 2025-01-01: 17 negativeWeek of 2025-02-01: 228 positiveWeek of 2025-02-01: 16 negativeWeek of 2025-03-01: 295 positiveWeek of 2025-03-01: 15 negativeWeek of 2025-04-01: 183 positiveWeek of 2025-04-01: 12 negativeWeek of 2025-05-01: 214 positiveWeek of 2025-05-01: 9 negativeWeek of 2025-06-01: 236 positiveWeek of 2025-06-01: 19 negativeWeek of 2025-07-01: 288 positiveWeek of 2025-07-01: 16 negativeWeek of 2025-08-01: 211 positiveWeek of 2025-08-01: 15 negativeWeek of 2025-09-01: 175 positiveWeek of 2025-09-01: 9 negativeWeek of 2025-10-01: 234 positiveWeek of 2025-10-01: 11 negativeWeek of 2025-11-01: 207 positiveWeek of 2025-11-01: 19 negativeWeek of 2025-12-01: 362 positiveWeek of 2025-12-01: 14 negativeWeek of 2026-01-01: 382 positiveWeek of 2026-01-01: 20 negativeWeek of 2026-02-01: 200 positiveWeek of 2026-02-01: 13 negativeWeek of 2026-03-01: 283 positiveWeek of 2026-03-01: 13 negativeWeek of 2026-04-01: 253 positiveWeek of 2026-04-01: 12 negativeWeek of 2026-05-01: 206 positiveWeek of 2026-05-01: 16 negativeWeek of 2026-06-01: 250 positiveWeek of 2026-06-01: 16 negativeWeek of 2026-07-01: 337 positiveWeek of 2026-07-01: 20 negativeWeek of 2026-08-01: 190 positiveWeek of 2026-08-01: 12 negative
Weekly review counts (Steam review histogram). Positive above the line, negative below.

Players online

124452026-08-06 21:00 — 103 players2026-08-07 05:00 — 62 players2026-08-07 13:00 — 84 players2026-08-07 21:00 — 107 players2026-08-08 05:00 — 63 players2026-08-08 13:00 — 86 players2026-08-08 21:00 — 117 players2026-08-09 05:00 — 69 players2026-08-09 13:00 — 97 players2026-08-09 21:00 — 114 players2026-08-10 05:00 — 45 players2026-08-10 13:00 — 84 players2026-08-10 21:00 — 80 players2026-08-11 05:00 — 52 players2026-08-11 13:00 — 81 players2026-08-12 21:00 — 71 players2026-08-14 04:00 — 53 players2026-08-15 12:00 — 85 players2026-08-16 20:00 — 100 players2026-08-18 03:00 — 66 players2026-08-19 11:00 — 73 players2026-08-20 18:00 — 100 players2026-08-22 02:00 — 70 players2026-08-23 09:00 — 76 players2026-08-24 17:00 — 106 players2026-08-26 01:00 — 83 players2026-08-27 09:00 — 74 players2026-08-28 17:00 — 117 players2026-08-30 01:00 — 100 players
Concurrent players, hourly average, last 30 days (census samples).

Price history

$4.99$0.492015-01-012026-07-092015-01-01 — best price $2.492015-06-22 — best price $4.992015-07-21 — best price $1.242015-12-01 — best price $4.992016-02-05 — best price $1.242016-03-25 — best price $4.992016-06-23 — best price $0.992016-08-01 — best price $4.992016-11-29 — best price $4.992017-06-22 — best price $0.992017-11-28 — best price $4.992018-02-15 — best price $0.992018-07-05 — best price $4.992018-12-20 — best price $0.992019-02-11 — best price $4.992019-11-26 — best price $0.492020-01-02 — best price $4.992020-11-25 — best price $0.992021-01-05 — best price $4.992021-11-24 — best price $0.992022-01-05 — best price $4.992022-06-23 — best price $0.992022-11-29 — best price $4.992023-03-16 — best price $0.492023-07-13 — best price $4.992023-09-19 — best price $4.992023-12-21 — best price $0.692024-03-21 — best price $4.992024-11-15 — best price $0.742024-12-04 — best price $4.992025-03-13 — best price $1.242025-07-10 — best price $4.992025-12-18 — best price $1.242026-03-26 — best price $4.992026-07-09 — best price $4.99
Lowest recorded price across tracked stores, per day (census snapshots).

Details

WindowsmacOSLinuxSingle-playerMulti-playerCustom Volume ControlsAdjustable DifficultyPlayable without Timed InputSave AnytimeValve Anti-Cheat enabledFamily Sharing

4 supported languages: English, French, German, Korean

Where its players are

Share of Steam reviews by language (top languages measured) — a proxy for where the player base lives.

Player tags

FPS1990'sActionAliensSci-fiClassicShooterMilitaryAdventureStory Rich

Census log

Computed from census-recorded observations only — dates are observation dates.

Players also track

Counter-StrikeHalf-LifeRogue WarriorWolfenstein: The New OrderDishonored

Similarity via IGDB.

Wikipedia ↗Official site ↗