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:
Overwhelmingly Positive - 95% of the 448 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (6,024) - 93% of the 6,024 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 (17)

10 October

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.
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14 September

Alien Swarm: Reactive Drop Update Released

  • Fixed bots listen to everybody's GO command. Now they only listen to their leader.
  • Fixed deagle's shooting prediction
  • Improved bot re-assigning. Previously if player took a break or disconnected his marine(s) was assigned to a random player. Now marine(s) is assigned to a player with the biggest number of bots assigned.
  • Improved alien-to-alien collisions. Prevent rangers, shamans and parasites from blocking other aliens movement. Fix burrowed aliens having incorrect collision group and blocking other aliens
  • Add rd_horde_two_sided cvar. If 1 and Onslaught is enabled a 2nd horde will come from opposite side, e.g. north and south. This cvar doesn't change horde size.
  • Fixed bots being easily interrupted while welding
  • Added "FireRate" keyvalue to asw_sentry_top_cannon
  • Director ignores disabled escape triggers. Normally, the director would avoid spawning aliens inside escape triggers and avoid spawning aliens anywhere if marines were in one, but this causes problems when a disabled escape trigger covers a large area, such as the entire map of as_paranoia3.
  • Added func_rd_no_director_aliens brush entity
  • Fixed small visual artifacts on Cold Catwalks map
  • Removed the unused asw_ammo_satchel_bonus cvar

Source Code was moved to a new URL:
Download it from Bitbucket
More info
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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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