Viewers who tuned in to “Treehouse Of Horror XXVI” on The Simpsons last weekend no doubt noticed that Bart, Lisa, and the other residents of Springfield looked a bit different in the show’s extended couch gag. That’s because the introduction was animated by John Kricfalusi, creator of The Ren & Stimpy Show, and he redesigned the characters in his own signature style. As both a student of cartoon history and a mentor to up-and-coming animators, Kricfalusi has always been generous about sharing the tricks of the trade with his fans, usually through his John K Stuff blog, and this latest Simpsons project (he already did a couch gag for the show once before) is no exception. On Wednesday, Kricfalusi posted a whole mess of “Treehouse Of Horror” storyboards and sketches. In the segment, Bart and Lisa are menaced by a giant zombie Frank Grimes, who rises from the grave while the Simpson children are trick-or-treating. In keeping with John K’s love of old cartoons, Bart seems to be wearing a vintage Huckleberry Hound mask. The introduction is set to a specially composed song, and the lyrics are also represented on the boards.