Executive Meddling: The later episodes were toned down, Mainly due to the earlier episodes showed deathly situations that were seen as too dark and scary for a kids show witch explains the Deus ex Machina plot point which is the Ghost Trap.
Keep Circulating the Tapes: The show had only six episodes released on VHS in the United States and has zero DVD releases. Thirteen episodes have been released on DVD overseas but the rest of the series is no where to be found. The only places the series can be found are on YouTube and torrents (though most of the episodes are recordings from when the show was on Toon Disney, so some scenes of horror may be edited). However, the show can now be watched on Hulu.
The Merch: Trendmasters released action figures and role-play accessories. The most notable of these were the deluxe figures, which featured battery-powered packs with light and sound.
Recycled Script: It's odd how difficult Egon found it to tell Janine he loves her in the climax of "The Crawler," considering they went through the exact same situation in the original series episode "Janine, You've Changed."
What Could Have Been...: The show was originally planned as a series-wide Myth Arc revolving around a coming war in the spirit world between Super-Natural Ghosts (Dead Humans) and "Pera-Natural Ghost (Ghouls)" (spiritual entities like Gozer who were never alive to begin with). Originally written as Demons (but that was nixed early on to avoid offending anybody's religious sensibilities) that threatened to spill over and destroy the Earth. Also, Egon would have long since quit his job at the university to become a mystic and travel through the afterlife (losing his ability to speak english and speak in an unknown ghostly language), only returning to the world of the living to warn people about the war. Janine would have been the teacher and it would have been her who put the group together.
The early Working Title was "The Super Ghostbusters" which was dropped in early development, so early that the crew working on the show doesn't remember that the show was ever called that, but early promotional material◊proves it was◊. However in some TV listings the show was confusingly called "Ghostbusters Dark".
An early video promo shows a ghost trap that used three arms as a cover instead of the bland three-piece dome cover seen in the final version with fans did not like.
This early logo◊ that was found on a animation website shows rivets in the red 'Ghostbusters'' logo, which were removed in the final version. Even the word "Extreme" is stylized in a manner not seen anywhere else. This rivet logo would actually appear in the series itself; seen on the firehouse in the episodes "Home Is Where The Horror Is" and "Moby Ghost".
According to Maurice LaMarche, Frank Welker was approached about reprising Slimer. However, the recording sessions were at night in order to accommodate the schedules of cast members who worked on live-action projects. Since Welker's schedule was busy enough as it was, he opted to just step aside and gave them his blessing to recast Slimer. However, Welker did return to voice Ray Stantz in the last two episodes.
Garret's nightmare in "In Your Dreams" was originally going to be a lot worse. It was going to be his mother torturing him with a cattle prod! The Sandman was planned to appear in this episode too but never did.