Phantasmagoria is a video game for those wondering what phantasmagorical is referring to.
The root word (phantasmagoria) actually goes back to the 1800s: https://www.etymonline.com/word/phantasmagoria
Definition is here: https://www.merriam-webster.com/dictionary/phantasmagoria
“an exhibition of optical effects and illusions; a constantly shifting complex succession of things seen or imagined (a scene that constantly changes); a bizarre or fantastic combination, collection, or assemblage”