The biggest surprise The Passing will deliver will be the meeting between the actual survivors and the ones in the original title – but Valve decided against offering too many details regarding their meeting. They did say, however, that the upcoming L4D2 DLC pack will introduce a new co-op campaign, new
arenas for Survival, Versus and Scavenge mode and introduce a new co-operative challenge mode of play. The Passing will also include a new “uncommon common” zombie class, melee weapon, and firearm. Again, specific details were not offered, but I am sure they’re coming.
“The Passing will become the most important campaign in the Left 4 Dead story, as all the Survivors are being called together in one campaign,” said Doug Lombardi, VP of marketing at Valve. “It will also be a huge offering of new gameplay content, with something new for every game mode plus a new uncommon common and weaponry.”
All in all, it sounds really great, so I think it’s fair to say that Left 4 Dead 2: The Passing will be a really great and anticipated content pack.