The Hatless Update was a major content update for Team Fortress 2 and the update included changes originally tested in the Team Fortress 2 Beta such as the coaching and voting systems, Training Modes for the Demoman, Engineer, and Spy, Badlands' King of the Hill mode, and several item tweaks. Other additions were the introduction of styles, dynamic model loading, and the association between servers and Steam IDs. Bots had their AI improved and duels were given the option of being class-specific. The painting and voice chat systems were also improved. A 'Sort by Rarity' option was added to the Backpack for sorting items.