The official launch of Cold Stream is here at last and with it comes a huge list of changes. All of which are applied to the campaigns ported from Left 4 Dead 1, including Crash Course, Death Toll, Dead Air and Blood Harvest. All those campaigns have suffered some major bugs for some time, especially for compatibility in versus mode and removing often used glitches or exploits. Additionally Cold Stream has a few changes too at this late stage. Finally, all mutations are now accessible via the main menu. Full change-list- Steam news.