Where did the river of pink slime come from?

Question

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In the sequel the Ghostbusters discover a river of pink slime underneath Manhattan.
The slime reacts to emotions, positive or negative, and can therefore be used for good or bad.

Initially I thought the movie's villain, Vigo the Carpathian, was somehow responsible for the slime's creation, but because of it's 'neutral' characteristics I was wondering whether it had a different origin.

My Question:

• Was Vigo behind the creation of the pink slime or did it come from somewhere/someone else?

Answer 1

From the Ghostbusters Wiki:

The origin of the Mood Slime is tied to a juvenile Sloar, held in Shandor's Island, beneath the Hudson River.

Before his death, Ivo Shandor and his Cult of Gozer had somehow lured the young Sloar from its home hell dimension and imprisoned it in our world within a Ghostworld pocket at the heart of Shandor's island mansion. Fueled by hatred, bile and anger the creature produced a steady stream of Black Slime.

Ivo Shandor, through experimentation and using equipment decades ahead of it's time, converted the Black Slime into what became known as the Mood Slime, which was then pumped directly into New York's sewers and abandoned tunnels, possibly as a means to help Gozer's crossing over.

This act was later used by Vigo to his own advantage.