Treehouse of horror ideas.
One where the Simpsons celebrate in each story the different holidays celebrated on October 31. Firstly Bart’s story is Halloween, trick or treating and Halloween parties. Second story is Oscar’s and it is about the holiday of Mexican day of the Dead festival. Finally Lisa’s story is about the holiday of Samhain (And Samhain from the real ghostbusters cartoon). Then Ned wants to do a fourth story observing All Saints Day. The Simpsons refuse because the episode is always three stories. Oscar relents if Saint Bartholomew will be there.
One story of a trio about onryō, Japanese vengeful ghosts. Where the Simpsons are terrorised by Sadako from the Ring and try to hide in the Grudge house and encounter Kayako. Then Sadako catches up with them but the vengeful ghosts fight each other over the Simpsons. The Simpsons go to leave the occupied ghosts but somehow they combine, or as Oscar puts it fusion danced into a composite spirit called Sadakaya.
An opening based on the Simpsons treehouse of horror compilation YouTube poop. Marge is at the red theatre/school assembly hall to warn about the episode being scary again but Oscar is patting a baseball bat menacingly. Then the classic graveyard opening credits with spooky song of scary songs like the twilight zone theme, Vincent Price’s laugh from Thriller and scary sounds. Then a couch gag.