From Team Fortress Wiki
Using the Fabricate Halloween Headgear recipe once yielded a 50% chance of crafting either a Voodoo Juju or Spine-Chilling Skull. As of the Very Scary Halloween Special Update, this is no longer possible as the recipe only results in one of three 2011 Spine-Chilling Skulls.
- [Undocumented] Added this item to the Mann Co. Store
- [Undocumented] Some untradable Spine-Chilling Skulls were made tradable.
- Fixed the Spine-Chilling Skull not appearing when equipped by Soldiers.
- [Undocumented] The Spine-Chilling Skull and Voodoo Juju are no longer craftable.
- Like several other Halloween hats, the Spine-Chilling Skull does not have a randomly selected level when crafted or purchased. The level of the Spine-Chilling Skull is always level 31, because Halloween is on the 31st of October.
- When the Spine-Chilling Skull is moved around in the backpack, it will make a paper bag sound similar to the Halloween Masks, the Mildly Disturbing Halloween Mask, the RIFT Well Spun Hat Claim Code, and the Summer Shades.
- Due to an error in the crafting system, a few Spine-Chilling Skull hats that were crafted early on during the Scream Fortress event are tradable, without the use of Gift Wrap. This error has since been fixed, but a Spine-Chilling Skull crafted during this time will remain tradable.
- On October 11, 2011 a blog post was released which detailed the process of modelling the Spine-Chilling Skull. The post indicates that the Skull is based on the Gremlin Noise Maker.