Muncher is a free-floating metal-munching ghost that came from the mines near Summerville area.
The creature loves to chew down on anything metal it can get its hands on. Somewhat smart, but more of a pest than an active threat.
In the present, Muncher was first seen by Phoebe and her classmate Podcast. They met up with Trevor in the Ecto-1 and then went after Muncher in Summerville. They discovered Muncher trying to eat a fire hydrant and the kids made their presence known by accident. It removed the water cap, causing water to erupt from the hydrant, and flew away. It was then chased by the kids throughout Summerville. Phoebe fired away at it with a mounted Proton Pack on the Ecto-1's gunner seat.
- IGN YouTube "Ghostbusters: Afterlife Director Jason Reitman on Fan Service and Revealing the Movie's Secrets" 3:53-4:09 11/13/2021 Jason Reitman says: "Josh and I ran into each other on the Sony lot and I was like, "Hey, do you want to come voice this ghost?" And he was, "Yes!" And he literally just walked in the room. We were literally in a room at the time. He walked right in, he started doing sounds and-and that is where the sound of Muncher came from."