The title of this article is a conjectural. Though the topic is found within The Simpsons universe, a proper name is not available.
The Past Horrors couch gag is the fourth couch gag of Season 11.
The family members (mostly) appear as they have in previous Halloween episodes: Homer is a jack-in-the-box (from 8F02), Bart is a mutant fly (from 5F02), Marge is a witch (also from 5F02), and Maggie is an alien (from AABF01); Lisa, an ax murder victim (the only one not based on a previous episode), comments on the lackluster Halloween special hosted by Kang and Kodos ("What do aliens have to do with Halloween?"). Maggie yells in Shaggy Voice, "Silence!" and vaporizes Lisa with her ray-gun. (Halloween episode)