User blog comment:Werewolfhell/Left 4 Dead Eleventy Blog 2/@comment-3137455-20091113204210

The players are split up into 2/3/4 teams of the special "Leader Infected" (Armed with an old WW2 LMG and Bile Bombs), they have to incapacite survivors and then bite them, infecting them. Its the only gameplay mode where there are no playable survivors.