The fourth annual Scream Fortress event goes live today in Team Fortress 2 and runs until November 8. This year pits players against the wizard Merasmus, who is in possession of the Bombinomicon. Merasmus inhabits a new King of the Hill map, and he has booby trapped the control point with the Wheel of Fate which spins every time the point changes hands. The item drop during this event consists of spells that can be used to alter other items in your stash. A new Mann vs. Machine map, Wave 666, has also been added and will be populated with zombies instead of robots.