Call of Duty Modern Warfare 2 and Warzone are adding a brand new mode to get players into the Halloween-themed. The Haunting is a new limited-time mode arriving with Season 6 adding a dark theme to the Warzone map with zombies and monsters to combat as well. The Haunting limited-time mode is coming to Call of Duty Modern Warfare 2 and Warzone with Season 6 on October 17.