Ghostbusters Reboot: 29 Easter Eggs, References & In-Jokes
9. The Big Bad
As revealed by one of the Mattel tie-in toys before the film even came out, the final big bad of the film - or more accurately, the final form of mysterious villain Rowan (who was entirely absent from the marketing, obviously) - is the familiar ghost from the Ghostbusters' own logo.
In the same way that the original Ghostbusters are invited to choose their own nemesis by Gozer and Ray attempts to choose a harmless image from his childhood, the new team's "idea" of a ghost is used against them. Rowan takes the form of the cartoonish ghost, inverting their use of him in their logo, and turns him into a monstrous, giant version.
Inevitably, he is undone when he's shot in the non-existent testicles, presumably suggesting that Rowan gave his creation sensitive genitalia for no apparent reason.