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 171 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,812) - 93% of the 6,812 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 (23)

April 20

Alien Swarm: Reactive Drop Anniversary Update - April 20, 2018

Today marks the 1 year anniversary of Reactive Drop's release! Along with that comes an update. We've added a few new weapons, a new seventh promotion and bug fixes for you all to enjoy.

Special thanks to Sk1p for creating brand new models for Heavy Rifle and Medical SMG as well as GUI icons for them.

  • Add asw_weapon_gas_grenades
  • Add asw_weapon_heavy_rifle
  • Add asw_weapon_medrifle
  • Add 7th promotion
  • Increase level cap to 34 to accomodate the 3 new weapons
  • Fix bots getting stuck in sentries
  • Fix alien_selection SizeScale for asw_drone_uber
  • Add couple CHATTER_GRENADE lines for Wildcat
  • Add new VScript functions
    • CBaseEntity
      • GetLocalOrigin() //Returns the Entity position in the world relative to the parent as a vector
      • SetLocalOrigin( Vector position ) //Moves the entity to this global position vector relative to the parent
    • CASW_Alien & CASW_Buzzer
      • ElectroStun( float duration ) //Stuns the alien
      • Freeze( float freezeTime ) //Freezes the alien
    • Global
      • DropFragGrenade( float damage, float radius, Vector position ) //Drops a frag grenade
      • DropGasGrenade( float damage, float dmgInterval, float duration, float fuse, Vector position ) //Drops a gas grenade
      • DropIncendiaryGrenade( float damage, float radius, Vector position ) //Drops an incendiary grenade
      • DropStunGrenade( float damage, float radius, Vector position ) //Drops a stun grenade
    • GameEvents
      • weapon_fire //Event fires when a marine fires a weapon
      • weapon_offhand_activate //Event fires when a marine activates offhand item
  • Fix missing Cvar dedicated server warning - Fixes the "ConVarRef rd_weapons_regular_class_unrestricted doesn't point to an existing ConVar" warning for dedicated servers.
32 comments Read more

March 30

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

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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