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 227 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,644) - 93% of the 6,644 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 (21)

14 March

Alien Swarm: Reactive Drop Update - March 14, 2018

This is mostly a bugfix update. Most notably it fixes an issue with aliens and bot marines attacking the scanner on Hostile Places mission(see picture above), Level One challenge and leaderboards for Bonus Missions.

List of our know issues and feature requests is available here

Change log
  • Fix rd_hp_regen affecting incapacitated marines
  • Fix Bonus Mission 4 and 5 leaderboards are not being populated
  • Reset Bonus Mission 1 leaderboard
  • Add Change Mission button in Singleplayer lobby
  • Fix Steam Overlay issue in lobby. Fixes an issue where if the Steam Overlay is disabled, clicking on any player name and choosing to open his/her profile wouldn't open a window. Fixes getting stuck if trying to open the window when the chat HUD is active.
  • Fix "-rd_max_depth_texture_shadows 8" startup argument not working as expected. "-rd_max_depth_texture_shadows 8" startup argument can now be used to increase the number of high quality shadows drawn on screen at the same time. Useful when rd_flashlightshadows 1
  • Update rd_infinite_ammo. It no longer affects the medguns or fire extinguisher. Use "rd_medgun_infinite_ammo" and "rd_fire_extinguisher_infinite" respectively.
  • Fix weapon insta-reload if dropped. Fixes an issue where if a marine begins reloading a weapon and then drops it, upon picking the weapon back up it will instantly finish reloading.
  • Fix rd_weapons_extra_class_unrestricted working incorrectly
  • Add new VScript functions
    • CBaseEntity
      • StopSound( string soundName ) //Stop sound from entity
    • Global
      • AddThinkToEnt( handle entity, string funcName ) //Adds a late bound think function to the C++ think tables for the obj
      • GetListenServerHost() //Get the host player on a listen server
      • IsDedicatedServer() //Returns true if this is a dedicated server
  • Fix asw_spawn_buzzer description typo
  • Fix asw_buzzer alien_selection.txt KeyValues. Flammable, teslable and other keys now properly work for asw_buzzer definition
  • Fix m_iMaxHealth not set for some aliens. The aliens affected are; asw_harvester, asw_mortarbug, asw_parasite and asw_shieldbug.
  • Add Cvars to set aliens' default health. Added "rd_harvester_health". Added "rd_parasite_defanged_health". Added "rd_parasite_health". Added "rd_shieldbug_health"
  • Fix Level One challenge allows picking any extra item
  • Fix npcs attacking npc_cscanner. NPCs will no longer attack the npc_cscanner on rd-par2hostile_places.
  • Make rd_max_marines non cheat var. It is now possible to host dedicated server with e.g. 4 playable slots and other slots being spectators.
  • Fix cl_selectm can be used to select more than rd_max_marines allows. Players could use cl_selectm console command to select more marines than the current challenge allows. E.g. cl_selectm 0 5 will select Sarge for 5th slot. This didn't work if slot was specified as -1
  • Print a message in chat if rd_max_marines limit is reached. When player tries to select a marine when rd_max_marines is enabled and there are no free slots left a message will be printed in chat saying why player can't select a marine.
  • Add rd_extinguisher_dmg_amount Cvar. If set higher than zero extinguisher projectiles will cause damage to aliens or marines.
  • Fix asw_stim_time_scale. It can now be set above 0.35 without breaking slomo_breath.wav.
  • Fix swarmopedia's materials for boomer and parasite. Previously they were giving red errors in console when Swarmopedia was opened
15 comments Read more

23 February

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

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Haikü created these some time ago but we couldn't decide which one looks better. Help us to decide by voting for the artwork item you like more.

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.
170 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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