IMHO.

Half-Life: Opposing Force vs Half-Life: Source

Half-Life: Opposing Force and Half-Life: Source both land in Action on Steam, which is why they keep getting compared. The comparison below is built from each game's Steam metadata — release year, genres, categories, Steam Deck status, price, and review score — refreshed daily by imho.run's scraper. Headline differences: Both are Action games on Steam. Half-Life: Opposing Force (1999) is 5 years older than Half-Life: Source (2004). Half-Life: Opposing Force scores higher on Steam reviews (95.4% positive) than Half-Life: Source (64.2% positive). No login or purchase needed — scroll for the full table, the verdict FAQ, and links to ranked similar games for both titles.

Which should you pick?

Choose Half-Life: Opposing Force

Choose Half-Life: Opposing Force if you want the Multi-player, Custom Volume Controls, and Playable without Timed Input side of the pairing. On Steam, it carries the stronger Steam consensus at 95.4% positive across 13,108 reviews.

Choose Half-Life: Source

Choose Half-Life: Source if it's the newer release (2004) and ships with the modern feature baseline. 7,832 Steam reviews back the pick.

Both Half-Life: Opposing Force and Half-Life: Source sit in Action on Steam, so either pick lands in the same broad neighborhood. Use the side-by-side table for the feature view, or follow the "Games like" links below to see ranked alternatives for either title.

Side-by-side comparison

Half-Life: Opposing Force vs Half-Life: Source — Steam metadata comparison
Half-Life: Opposing Force — Steam game coverHalf-Life: Opposing ForceHalf-Life: Source — Steam game coverHalf-Life: Source
Released19992004
GenresActionAction
PlatformsWindows, macOS, LinuxWindows, macOS, Linux
Steam DeckDeck PlayableDeck Playable
Price4.99 USD9.99 USD
Steam reviews95.4% positive (13,108 reviews)64.2% positive (7,832 reviews)
MultiplayerMulti-playerSingle-player only
DevelopersGearbox SoftwareValve

Side by side

Half-Life: Opposing Force vs Half-Life: Source — FAQ

Which is better, Half-Life: Opposing Force or Half-Life: Source?
On Steam reviews Half-Life: Opposing Force scores higher (95.4% positive) than Half-Life: Source (64.2% positive). Both have enough reviews to trust the signal, so for players using reviews alone, Half-Life: Opposing Force is the safer pick. Genre fit still matters — check the side-by-side table for the categories each game lands in.
Should I play Half-Life: Opposing Force or Half-Life: Source first?
If you want chronology, Half-Life: Opposing Force (1999) came out before Half-Life: Source (2004). If neither is a sequel to the other, order doesn't really matter — start with whichever fits your current mood, since both share enough on Steam to make either a reasonable opener.
Are Half-Life: Opposing Force and Half-Life: Source similar?
They overlap on Action on Steam, so the catalogue groups them together — but "similar" depends on the specific mechanics. Use the genre + category rows above to decide whether the overlap matches what drew you to the one you've already played.
Does Half-Life: Source have multiplayer like Half-Life: Opposing Force?
No. Half-Life: Opposing Force supports multiplayer on Steam (Multi-player), while Half-Life: Source is listed as single-player only.
Half-Life: Opposing Force vs Half-Life: Source (2026) · imho.run