The maps
mvm_coaltown, mvm_decoy, mvm_mannworks, mvm_bigrock, mvm_rottenburg, mvm_mannhattan and mvm_ghost_town ship with the game. Start the server on one, or change to it: the server switches into MvM by itself and loads the map's default mission.
Players and plans
MvM is for six defenders, but the robots are the server's own bots and take player slots too: run it with Max Players at 32 (Valve's own MvM servers do), which you set in Deployment Settings on any plan. Players join through the console or the server browser like any community server.
Tip:On Flux, pick an mvm_ map in the Maps tab, or set it as the starting map in Deployment Settings.
Frequently asked questions
How many players can play MvM?
Six, on the defending team. The robots are bots run by the server, which take slots too: set Max Players to 32.