Valve just announced a new game mode for Team Fortress 2 called Mann vs Machine. It's a 6-man co-op mode and players will be facing against waves after waves of robot enemies attempting to plant a bomb on a Mann Co. building. The co-op mode will include new maps, achievements, and objectives to complete in order to earn some loot. It's horde Team Fortress 2 style. What's great is that this mode goes live tom, Aug 15. Check the trailer for Mann vs Machine below.
Check out the official site for more information.