Valve has released an update this week for the recently introduced co-op mode in Team Fortress 2, Mann vs Machine.
The update brings changes to matchmaking and difficulty in Mann vs Machine. First up, there are two new Tours of Duty (MvM's name for difficulty modes). One of the new tours is more difficult than the normal mode, while the other is easier. Both tours feature some new loot that can be acquired during the match. All told, Mann vs Machine now features three Tours of Duty...
- Operation Oil Spill (Easiest)
- Operation Steel Trap (Harder)
- Operation Gear Grinder (Hardest)
In addition to the new Tours of Duty, Valve has also updated Matchmaking with some new options.
The improvements are going to make it much easier to get into a group with other players, letting you select multiple missions when you begin your matchmaking search. Additionally, after you complete the mission, you will be sent back to the matchmaking screen with your group, allowing you all to quickly jump into a new match together.
Check out http://www.teamfortress.com/ for more information on this week's update.

