Egon Spengler him, which leaves him a little flustered. He celebrates his 40th birthday during this series, which would put him in his late twenties when "The Real Ghostbusters" began. Age is the largest factor causing Spengler to having transition from active ghost hunting to a mentorship role; in one episode where the original Ghostbusters guest starred on an episode the audience clearly sees middle adulthood has affected the speed and weakened the stamina of the original Ghostbusters. Although Egon Spengler does not appear in the 1990 "The Earth Day Special", his character and status as a Ghostbuster is mentioned, and Harold
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.