Egon Spengler Oswald Spengler and a classmate of Ramis at Senn High School, Egon Donsbach, a Hungarian refugee. Christopher Walken, John Lithgow, Christopher Lloyd and Jeff Goldblum were all considered for the role of Egon Spengler, before Ramis, who had gotten close to the character while writing him, felt compelled to play it himself. LaMarche stated that when he auditioned for the part of Spengler in "The Real Ghostbusters", he was asked not to do an impression of Ramis, which he ignored because impressions were one of his strengths as a performer, and there was no other way he could imagine properly
Egon Spengler intellect switched with Slimer's. He has however, ceased his sugar junkie ways, only to briefly be tempted by a candy store when in Slimer's body (a likely fact that Slimer was an overt glutton). It is revealed in "The Boogieman Cometh" that, as a child, Spengler was stalked by the boogieman, a supernatural monster that fed on the fear of children and hid in their closets, and was particularly fond of Spengler's fear; it was these encounters with the creature that inspired Spengler to study the paranormal, and as an adult, he would battle the Boogieman twice and defeat him.