Co-operative multiplayer game and complete code base available for free.
That One Thing
The corridor where the swarm pours in from both ends and your medic is the only reason anyone makes the extraction.
Alien Swarm clears the PlayBound Bar as a complete, free Valve co-op shooter with campaign polish that still holds up — and Reactive Drop keeps the swarm alive when you want the modern continuation.
Worth the cost
Free, or regularly available for $15 or less. Good developers deserve to be paid, and optional cosmetics, expansions, and premium extras are welcome. But we won't list games that sell competitive advantages, disguise a trial as free, or charge again to finish the core experience.
Ready to play
Playable and satisfying today. It can be unfinished; it cannot be unfun. We love supporting indie developers, but prototypes, broken releases, and promises of a future game do not make the cut.
Tested by PlayBound
We install it, launch it, and play it ourselves. We've spent hours building definitive editions and making multiplayer work, because a store-page claim is not the same as a game we can confidently put in front of you.
That One Thing
Every game needs that one thing we'd excitedly tell our friends about. It might be the mechanics, story, art, soundtrack, controls, community, or the way it brings people together. If it doesn't have one, it doesn't make the catalog.
Alien Swarm last verified against the bar on . Read the full standard →
Alien Swarm is Valve's top-down co-op shooter: four marines drop into claustrophobic corridors, burn through ammo, and try not to get overrun by a hive that never stops coming. Classes matter — officer, special weapons, medic, tech — and so does not shooting your teammates when the hallway fills with parasites.
It shipped free on Steam in 2010 as a polished Source engine campaign with bots if friends are scarce. Missions are short, readable, and built around teamwork: cover the tech while they weld, keep the medic alive, and clear nests before the next wave spills out. The campaign is complete; there is no shop gate between you and the ending.
On PlayBound we list the original free Steam build. Controller support is partial on classic Swarm (console exec / Steam Input help); the community continuation Alien Swarm: Reactive Drop is the better pad-first option when you want official full controller support and a still-active multiplayer scene.
We picked Alien Swarm because it is a finished Valve co-op campaign that costs nothing, plays cleanly in a short evening, and still teaches the same squad habits that later free shooters borrow. It is free gaming with a capital V.
Great if you want
Look elsewhere if
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Minimum
Windows 7 / Vista / XP · Pentium 4 3.0 GHz · 1 GB RAM (XP) / 2 GB (Vista+) · DX9 GPU 128 MB SM 2.0 · 2.5 GB storage
Recommended
Windows 7+ · Core 2 Duo 2.4 GHz · 2 GB RAM · DX9 GPU SM 3.0 (GeForce 7600 / Radeon X1600 or better) · 2.5 GB storage
Yes. Valve released it free on Steam. PlayBound hands off to Steam for download and updates — there is no separate PlayBound-hosted package.
Alien Swarm is Valve's original 2010 campaign. Reactive Drop is the free community continuation with more content, active multiplayer, and official full controller support. Both are listed separately on PlayBound.
Partially. Classic Swarm often needs Steam Input or console commands. Reactive Drop ships official full controller support.
The campaign supports local play with bots. Online co-op needs Steam and a network connection.
| Move | W, A, S, D |
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More screenshots and trailers live on the official Alien Swarm site.
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