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 - 90% of the 173 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,807) - 93% of the 6,807 user reviews for this game are positive.
Release Date:
20 Apr, 2017

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Play Alien Swarm: Reactive Drop


Recent updates View all (23)

30 March

Alien Swarm: Reactive Drop Update - March 30, 2018

This update addresses issues with HiDPI displays and display scaling, bots and adds a new cvar for use in add-ons.

  • Fix marine bots collision group. Fixes issue where marines were teleporting through elevators, and falling to the ground below the ship at the start of rd-til8comcenter.
  • Add rd_queen_hud_suppress_time Cvar. It is used to suppress the Swarm Queen's health HUD if not damaged for this long seconds (-1 to always show).
  • Fix title of Bonus Mission 5.
  • Fix bots don't get into train in tft3Spaceport map
  • Improve nodegraph in tft3Spaceport
  • Update reactivedrop.exe with HiDPI aware flag. This should resolve numerous issues with HiDPI displays or when Windows text and apps scaling is set to be above 100%. Previously users have had game window opened in a size(resolution) that is bigger than user's monitor resolution and thus were unable to change the resolution and any options(because most of UI was off screen).
We're also looking for a person capable of drawing new promotion icons which fit the original Alien Swarm style. If you feel you're up for the task please create a new discussion in our feedback subforum where we can discuss the details. Feel free to submit your designs and ideas for the new promotion icons.
13 comments Read more

23 March

Alien Swarm: Reactive Drop Update - March 23, 2018

This update brings bug fixes and a new VScript function for use in add-ons.

  • Fix vindicator and devastator shotgun shell ejection. Previously only one shotgun shell was ejected after multiple shots. Now each shot ejects an empty shotgun shell.
  • Fix aliens crowding on an incapacitated marine's body. When marine is incapacitated and other marines are not around aliens were piling up around the incapacitated body.
  • Fix grenade launcher's grenade colliding with bot marines
  • Make npc_cscanner not collide grenade launcher's grenades and players
  • Fix drones warping through marines in ASBI challenge
  • Added the following VScript function for CBaseEntity. PrecacheModel( string modelPath ) //Precache a model after the map has loaded.
  • Fix asw_buzzer SpeedScale. It's now possible to change the m_fSpeedScale for the buzzer
  • Fix Take A Break being greyed out on servers which have lobby disabled
12 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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