Co-operative top-down shooter game available for free. An epic bug hunt featuring a unique blend of co-op play and squad-level tactics.
Recent Reviews:
Very Positive - 94% of the 220 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,516) - 93% of the 6,516 user reviews for this game are positive.
Release Date:
Apr 20, 2017

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Play Alien Swarm: Reactive Drop


Recent updates View all (20)

February 23

Alien Swarm: Reactive Drop Update - February 23rd, 2018

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Thanks to Raymond Nondorf we now have a lot of new VScript functionality and cvars to power your most intricate mods.

This update brings all the changes from our beta branch into the release one. The main features include:
  • New VScript functions, NetProp Manager, cvars, game events to facilitate the creation of new exciting challenges.
  • Improved colonists support. BI Rescue mission from workshop will now properly work.
  • Graphics settings will now be set to High when the game is first launched on capable hardware.
  • Workshop's sound add-ons will now properly work. Sound cache will be automatically updated to prevent sound glitches.
  • Bots are now smart enough to revive fallen team mates in challenges which have reviving enabled(e.g. Rifle Mod).
  • Marines now have different colors in Team Deathmatch.
  • Bugfixes, optimizations and improvements.
  • Removed Orion's Threat campaign, its achievements, Bonus Mission 1 and associated content because of original author's request. Orion's Threat campaign evolved into an Adanaxis campaign which is currently available in workshop. Due to disagreements with the original author there are no current plans of integrating Adanaxis as an official campaign in Alien Swarm: Reactive Drop.
  • Bonus Mission 1 will now be Invisible Threat map by uradzimiru
  • Added bonus missions 4 and 5. Mission 4 being the tutorial mission Offline Practice(Landing Bay and Cargo elevator stitched in one) Mission 5 being the unsplit original Paranoia's mission 2 Hostile Places

The detailed changelog is available in our beta discussion thread.
Note: some workshop challenges may not work properly due to changes in cvars. They need to be updated by their authors to use new cvars.
136 comments Read more

January 17

Alien Swarm: Reactive Drop Beta Update - January 17th, 2018

We are starting a beta for testing new features and bug fixes.

The current beta update mostly contains new VScript functions and cvars which can be useful for modders in creating new and exciting game modes(challenges).

All the details about the beta update are explained in this discussion. Please subscribe to that discussion if you want to get notifications about new updates pushed into beta.

Note: If you switched your game to the Beta update you will be unable to connect to non-beta servers.
18 comments Read more

About This Game

Alien Swarm: Reactive Drop extends Alien Swarm, bringing more of everything: maps, aliens, game modes, guns... And most importantly Steam Workshop support.

  • Tactical co-op for up to 8 players with a top-down perspective
  • Steam Workshop support for community maps and challenges
  • New co-operative campaigns
  • Challenges: Modifications of the game, just like Mutations in Left 4 Dead 2
  • PvP: Deathmatch, Gun Game, Instagib, and Team Deathmatch
  • Singleplayer: Play with improved bots on all our official maps
  • New Aliens: HL2 antlion guards and more
  • New Weapons: Desert Eagle, Devastator, and Combat Rifle, with more to come
  • Over 100 Steam achievements
  • Leaderboards: compete with your friends for the fastest mission completion
  • Improved spectating: see hacking minigames and mouse movements in real time

System Requirements

    • OS: Windows® XP or above
    • Processor: Pentium 4 3.0GHz
    • Memory: 2 GB RAM
    • Graphics: DirectX 9 compatible video card with 128 MB, Shader model 2.0. ATI X800, NVidia 6600 or better
    • DirectX: Version 9.0
    • Storage: 4 GB available space
    • Sound Card: DirectX 9.0c compatible sound card
    • OS: Windows® XP or above
    • Processor: Intel core 2 duo 2.4GHz
    • Memory: 4 GB RAM
    • Graphics: DirectX 9 compatible video card with 128 MB, Shader model 2.0. ATI X800, NVidia 6600 or better
    • DirectX: Version 9.0c
    • Network: Broadband Internet connection
    • Storage: 6 GB available space
    • Sound Card: DirectX 9.0c compatible sound card
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