Slimer is perhaps the best recognized ghost in the Ghostbusters universe, having appeared in both movies, every episode of The Real Ghostbusters animated series, every issue of The Real Ghostbusters comic book series, and even had his own solo comic published by NOW comics. Slimer’s most recent appearance was in the 2009 Ghostbusters video game, and seems likely to appear in the upcoming film Ghostbusters 3.
Creation
Slimer was created by Dan Aykroyd and Harold Ramis when they wrote the original Ghostbusters film. They have stated him to be the ghost of John Bellushi