Alien Swarm: Reactive Drop - Steam Backup
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 . Challenges: Modifications of the game, just like Mutations in Left 4 Dead 2 . PvP: Deathmatch, Gun Game, Instagib, and Team Deathmatch .