Left 4 Dead 2 was originally criticized for the fact that it would be a sequel designed by Valve so that it could extract more money from fans while offering no real new content.

Of course, since the videogame was first announced, Valve has talked to the player community for the first Left 4 Dead and explained what it was trying to do with the sequel and why it needed to be a separate game. It seems that the concept of the boycott is now behind us and the title will probably be as big a success as the first one in the series.

The charge of lack of innovation has been further dispelled by the unveiling of the Scavenger Mode, which is set to again divide players into two camps, Survivors and Infected, with four players in each of the two.

The twist is that the Survivors are now aiming to escape the level but to find fuel cans spread around the area that must be poured into a generator. Doing this scores a point for the team and adds time to the game clock. The aim of the Infected is to stop them from scoring and beat their mark when they switch sides.

It's a nice twist because it opens Left 4 Dead 2 for very different strategies from those employed in the game modes inherited from the original title. The pressure of the clock ticking down will probably mean that the Survivor team will split up even more and might be more vulnerable as they search for the fuel cans and Survivors will need to work more on their own than as a team.

As long as Valve makes sure the game mode is customizable, it should be a blast and will deliver an experience that cannot be in any way replicated in the first Left 4 Dead.