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 208 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,482) - 93% of the 6,482 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 (19)

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

October 10, 2017

Alien Swarm: Reactive Drop Update - October 10th, 2017

  • Fixed asw_broadcast_camera. It no longer crashes all clients when it is disabled. Added a spawnflag for disabling player HUD. Players switch to first person mode while the camera is active.
  • Fixed Grenade Launcher's UI damage displaying 80(+80). Also fixed Sentry Cannon's description.
  • Fixed Grenade Launcher's grenade doesn't have smoke trail.
  • Added rd_pistols_min_delay cvar. If set to more than 0 will set the delay between each shot of Twin Pistols in seconds. 0.1 recommended, 0 is default.
  • Set rd_pistols_min_delay 0.1 for Level One challenge and PvP game modes
  • Allow setting alien orders via vscript. Added ClearOrders, OrderMoveTo, ChaseNearestMarine VSCRIPT functions for aliens and buzzers.
  • Allow vscripts to spawn grenade clusters. Added VSCRIPT function
    CreateGrenadeCluster(float flDamage, float flRadius, int iClusters, Vector position, Vector angles, Vector velocity, Vector angVelocity)
  • Allow attaching vscripts to aliens spawned by a spawner
  • Fixed speaker configuration is reset after game restart
  • Removed mapspawn.nut script file
  • Add rd_download_workshop_previews cvar. If set to 0 game will not download preview images for workshop add-ons during game startup which can increase performance in main menu if client is subscribed to lots of add-ons or uploaded lots of add-ons to Steam Workshop.
  • Fixed ammo satchel refusing to deploy ammo if there is a ceiling
  • Fixed deployed ammo not moving with elevators
  • Exposed CASW_Marine::IsInhabited and CASW_Marine::GetCommander to vscript
  • Fixed grenades doesn't have a smoke trail. Assault Rifle's grenade, Freeze Grenades, Hand Grenades didn't have a smoke trail on many maps because of incorrect initialization. Also fixed Prototype Rifle's grenade not having its electro effect.
  • Fixed a few out of bounds areas in Timor Station.
  • Added rd_increase_difficulty_by_number_of_marines cvar. Difficulty will be slightly increased for 5+ marines. This means alien speed, damage and health will be slightly increased.
  • Added rd_leaderboard_by_difficulty cvar. If enabled(by default) will display leaderboard for current difficulty level rather than mixing all difficulties in one. Stats website now also have this functionality enabled.
  • Fixed leaderboard stats are uploaded when watching demo
  • Fixed sv_maxrate is adjusted if it is set to 0. Since 0 means unlimited we don't want to adjust it to 60000 in this case when rd_adjust_sv_maxrate is set to 1.
  • Fixed a few out of bounds areas on Desert Outpost.
35 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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