They said monorail… but is it not the treehouse of horrors where Bart is feeling unimportant and gains the ability to read people’s thoughts ( I wanna say money paw) and can use his mind to turn them into wonky things? He turns Homer into a Jack in the box.

I remember a radio/tv announcer seeing something really strange happen during a baseball game or something - like the pitcher suddenly gets duck feet - announcer says like “and what do we say whenever something strange happens… it’s good Bart did that”

The whole town becomes terrified of him.