The Halloween event, also known as Scream Fortress, is an annual event when enchantments, hauntings, and family curses fall upon the world-wide facilities of Mann Co. during October and several days into November. First introduced in the The Terrifying Team Fortress Haunted Hallowe'en Special of 2009, Halloween events feature activation of Halloween-themed start screens, spooky sound cues, Halloween maps, soul-harvesting contract campaigns, Halloween cosmetics, Ghosts, and monsters, with Scream Fortress Patches adding new Halloween content.
Development of the Halloween event
The original Holiday-restricted Halloween events opened with a Major Update content patch and concluded 10 or so days later with removal of Halloween cosmetic effects.
Most of the individual Halloween Updates introduced new features to the Halloween event celebration, whether new maps, monsters, or mechanics, like magic spells or the Soul Gargoyle. Valve treated the first seven Halloween events as "major updates", each with an update page on the official Team Fortress website and a Comic of some form. From the beginning, Halloween events have been linked with continuations of the Team Fortress 2 Storyline, with the release of Zephaniah Mann's last will and testament and family portrait and the coupling of the Halloween comics with closely released main Storyline comics, notably the murders of Blutarch and Redmond and the crossovers of Merasmus. However, from the 8th annual event onward, no update pages or comics were published. The first six events released seven haunted maps (five developed by Valve), but the next four events released 12 Community maps and one Valve map.
From 2019 onwards, Valve has activated Halloween mode on the first of October, with the update arriving later that month. This allows players to play on the old Halloween maps before the next Scream Fortress update is out.
List of Halloween events