Alien Swarm: Reactive Drop

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: Bulldog, 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