Team Fortress trading essentially comes down to this: you have a hat, and someone else has a hat. You want their hat. You open the trading window and you swap hats. Everyone is happy and hattier. That ...

Mann vs Machine is Team Fortress 2's robot-slaying, wave-based, co-op game-mode. Though both TF2 and the MvM mode are free, those looking for a little extra challenge can buy tickets to access its ...