However, as in any source game, you can do this by adding -maxplayers 6 to the SRCDS command-line. 6 is a limit hard-coded into the game. Steam Database record for depot alien swarm content (DepotID or AppID:) xw0d1ry4t3.cf; srcds_run; xw0d1ry4t3.cf; xw0d1ry4t3.cf; bin music . Steam Database record for depot alien swarm content (DepotID or AppID: ) xw0d1ry4t3.cf; srcds_run; xw0d1ry4t3.cf; xw0d1ry4t3.cf; bin music. xw0d1ry4t3.cf; xw0d1ry4t3.cf; aswav; xw0d1ry4t3.cf; objectivecomplete. Go to the Tools tab in Steam and double click the "Alien Swarm xw0d1ry4t3.cf - console -game swarm +map lobby -maxplayers 4 -autoupdate.
HowTo: Set up Dota 2 LAN using Alien Swarm SRCDS
SourceMod: Half-Life 2 Scripting