Liste der Änderungen im Patch 1.6:

■3 new Multiplayer maps: Battery (mp_drum), Breach (mp_bgate), Revolution (mp_vodka)!
■New Nazi Zombie map: Der Riese (nazi_zombie_factory), an all-new Zombie map set in a secret Nazi research facility featuring the Pack A Punch Machine, Teleporters, and many more undead hordes!
■Exploits pertaining to Demo playback.
■Favorites list now ignores filter settings.
■Fixed S&D round counting error when roundlimit is reached.
■New feature: in-game Add to Favorites.
■Friends list: green online indicator.
■Starting the game in Safe Mode will no longer toggle the “Soften Smoke Edges” graphic option.
■Fixed various crashes.
■Mods: Client will no longer join a modded Co-op server via Game Invite unless they have that mod loaded.
■Mods: Client running a mod will be asked to unload the mod if they attempt to join an unmodded server.
■Mods: All singleplayer levels can now be run with a mod loaded.