Is this really the first thread about the DLC? I figured there would be more. I got it yesterday and played a couple of versus modes( one being the mutation) and beat it on the campaign. I got the impression from Valve like you said that the original survivors would play a bigger part. I played it in versus first which you don't get to see any of the originals except for fallen Bill. Then I played it campaign and was like ohhh now I see.
The mutation this week is just realism versus nothing special really. Wish it could have been something other than a game mode already offered.









