 Complete the following phrase:  Although Treehouse of Horror episodes are Halloween-themed, for several years new episodes premiered in November following the holiday, due to Foxs coverage of Major League Baseballs World Series. Season 12s Treehouse of Horror XI was the first episode to air in November. There have been several references to this in the show, such as in Season 15s Treehouse of Horror XIV where Kang looks at a TV Guide and says, Pathetic humans. Theyre showing a Halloween episode... in November! and Kodos replies Whos still thinking about Halloween? Weve already got our Christmas decorations up! The camera then cuts to a shot of the fireplace with Christmas decorations, and festive Christmas music plays over the opening credits. Season 21s Treehouse of Horror XX aired October 18, before the World Series, but the following years episode, Season 22s Treehouse of Horror XXI, aired on November 7. Season 23s Treehouse of Horror XXII aired on October 30, however, as the World Series which went the maximum of 