Saturn (Earth-8591)

Saturn is a limbo inhabited by corrupted spirits and sandworms.

History
When Adam and Barbara Maitland died, they returned to their apartment in 550 Central Park West, but once they entered it the apartment changed into a dark, sandy night that materialized into Saturn. Adam heard a sandworm and something sticking out of sand that grabbed both of them, but they were able to escape.

The noise started to grow in intensity, leading to a sandworm to pop out of the sand in an attempt to eat them, but Barbara was able to hit the sandworm, which shook its head, and was thus unable to kill the couple when they escaped through a door.

When fighting Betelgeuse, the Ghostbusters were almost killed by two sandworms, accidentally bringing one of the creatures to the physical world; ironically, the sandworm swallowed Betelgeuse alive, crashing through the floor, and giving the opportunity to imprision both of them with a muon trap.