Properties and behavior
Psychomagnotheric Slime is distinguished from ordinary ectoplasm by its sensitivity to emotion. A negatively charged sample absorbs ambient hostility and amplifies it back into the environment. A positively charged sample neutralizes negative energy, can sever ghostly possessions, and in sufficient volume can animate inanimate objects. Key properties documented across the primary and secondary canon:
Psycho-reactivity. The slime absorbs and amplifies surrounding emotional states. Shouting, insults, and aggression cause it to bubble and react violently; calm encouragement, singing, and music elicit a positive response.
Animation. Both positive and negative charges can animate inanimate objects, from a kitchen toaster dancing to Jackie Wilson to the Statue of Liberty marching from the harbor to Midtown. The behavior of animated objects reflects the emotional charge: negatively charged objects become hostile; positively charged ones tend toward the benign.
Portal generation. Concentrated negatively charged slime can open rifts for ghosts to cross dimensions and can significantly amplify a spirit's existing power. Vigo used the River of Slime beneath Manhattan for exactly this purpose throughout the events of Ghostbusters II.
Possession effects. Positively charged slime can drive out a possessing entity or weaken a corporeal manifestation. Direct contact with negatively charged slime fills a person with the stored negative emotions it has absorbed.
Kinetic aggression. Under strong negative influence, the slime can physically attack. Ray Stantz experienced this when he attempted to collect a sample from the River of Slime and it formed tentacles to reach for him.
P.K.E. signature. At the First Avenue site where slime had seeped through the pavement, Egon Spengler and Ray Stantz recorded 1,118 on the P.K.E. Meter and 2.5 GeV on the Giga Meter.
The slime appears in several hues. The naturally occurring strain in Ghostbusters II is pink. In Ghostbusters: The Video Game, Egon's refined growth medium produces a dark green variety, while the original pink strain still appears in multiplayer modes as a power-up. In The Real Ghostbusters continuity, the slime shifts to a yellow hue when used in specific circumstances. IDW Comics identifies yellow slime as a mild form of the substance and theorizes purple as a more potent strain.
Ghostbusters II
The slime first appeared in 1989 when some of it seeped through a crack in the sidewalk near Dana Barrett's apartment on East 77th Street. Contact with it animated Oscar's baby carriage, which rolled away on its own and stopped on First Avenue to avoid a bus. Ray was lowered on a rope through a hole cut in First Avenue, where he found the River of Slime, a massive subterranean flow running through the old Beach pneumatic transit tunnels. When he attempted to collect a sample, the river reacted and sent tentacles toward him.
A sample of the slime brought to the Ghostbusters' subsequent trial absorbed the negative energy in the courtroom and exploded, releasing the Scoleri Brothers. The team was reinstated, and Ray and Egon spent the following weeks conducting controlled experiments. They discovered it responded to emotional input in both directions: insults and harsh words triggered violent reactions; singing, supportive speech, and the music of Jackie Wilson produced equally strong positive responses. They also found it had physical consequences: negatively charged slime had animated Dana's bathtub, and a positively charged sample made a toaster dance. Peter Venkman named the substance "Mood Slime."
The massive concentration beneath Manhattan was feeding on the hostility of ordinary New Yorkers and being amplified by Vigo the Carpathian, who used it as an energy source, shielding agent, and assault weapon. As New Year's Eve approached, the slime rose to street level and triggered mass supernatural manifestations across the city. The Ghostbusters' proton streams could make no dent in the hardened slime shell Vigo had raised around the Manhattan Museum of Art.
The solution was positively charged slime, loaded into two Slime Blowers and used to animate the Statue of Liberty, which broke through the shell. Inside the museum, Ray and Winston Zeddemore used their blowers on Janosz Poha and on Ray himself after Vigo possessed him. The crowd singing outside provided enough ambient positive energy to neutralize the remaining slime, and when Vigo was finally defeated, the slime shell disintegrated and the supernatural activity across the city collapsed with it.
Nearly all of the Psychomagnotheric Slime disappeared after Vigo's defeat. Ray kept the last of it in a jar, and at some point it crystallized into several shards.
Ghostbusters: The Video Game
The in-game lore gives the slime a different origin.3 A juvenile Sloar, held captive in Shandor Island beneath the Hudson River by Ivo Shandor's Cult of Gozer, produced a steady stream of Black Slime fueled by hatred and anger. Shandor converted this Black Slime into the Mood Slime and pumped it into New York's sewer system, apparently as part of his preparations for Gozer's crossing. Vigo later took advantage of what Shandor had put in place.
By 1991, Egon Spengler had refined the substance into a self-replicating growth medium, the Plasm Distribution System. Using his knowledge of spores, molds, and fungus, he created an energetic medium that provided a continuous supply of positively charged slime from a small reservoir attachable to the standard Proton Pack. The pigment had changed from pink to dark green, and most of the emotive and portal-opening properties were reduced, though care was still needed when using it around punk, heavy metal, or hip-hop music. The positively charged version served primarily as a counter-agent for Black Slime, which was negatively charged and could create portals across dimensions.
The Real Ghostbusters
After the events of Ghostbusters II, the Ghostbusters collected samples of the Psycho-Reactive Slime. Experiments confirmed it responded to thoughts and emotions and could also grant a person limited ghostly powers such as flight. Egon Spengler never fully understood the mechanism behind this.
The team used the last of the slime on Janine Melnitz's birthday to rescue her and Louis Tully from a ghost called Poso. Peter Venkman was covered in the slime (yellow in this continuity) and smuggled into Poso's base in Ghost Town. After the rescue, the slime had grown attached to Peter. When he lost his temper, it turned red and began dragging him along with it until he calmed down, at which point it released him.
Ghostbusters: Frozen Empire
In summer 2024, Phoebe Spengler delivered a jar of Psychomagnotheric Slime requested by Ray to Ray's Occult Books. Slime Blowers and Psychomagnotheric Slime were also being actively researched by the Ghostbusters Engineer Corps, with Ruth Myers using a Slime Blower in the shooting range at the Paranormal Research Center.
Ghostbusters: Back in Town
When a green super slime turned up in the sewers in June 2022, Ray revealed to Phoebe Spengler that his jar of Psychomagnotheric Slime had crystallized. He introduced a crystal into a sample of the green slime, and Phoebe confirmed with a P.K.E. Meter that the slime was fully neutralized. With only the jar of crystals remaining, Phoebe theorized that proton streams passed through an affixed crystal would be altered in a way that gave them power to fight Madame Malveaux and her slime. Testing on a cockroach was successful, but the crystals burned out in extended combat. Phoebe used the last crystal, loaded into a modified ghost trap cone, to successfully capture Malveaux.
IDW Comics
The IDW Comics continuity treats Psychomagnotheric Slime as an ongoing tool rather than a one-time plot device.4 The Ghostbusters have identified it as a byproduct of the high ambient P.K.E. always present in a major metropolitan area, kept in check over time by the positivity generated by tourism and successful sports teams.
Uses across the series include: dousing an angry New Orleans mob to let the team reach their client; neutralizing a Ghost Fire Wall around Central Park; liberating Hart Island Ghosts from Vigo's control; weakening Hedylogos using negatively charged slime; and assisting the Teenage Mutant Ninja Turtles in exorcising Chi-You from Winston. A more compact device, the Slime Spritzer, was developed for situations where a full Slime Blower was impractical. Class notes from Ghostbusters 101 #4 describe standard field units as "20-gallon slime blowers (sometimes a lot of slime is needed to sever the bonds of possession)."
Studies with Jenny Moran confirmed Corporeal Class 4 manifestations are most affected by exposure. When exposed to sufficient positively charged slime, such entities revert to a standard ghost form, making them easier to shoot and trap. The series also establishes that using positively charged slime in a highly negative environment has a caustic effect on corporeal entities.
Production and special effects
Blair Adhesives supplied 13,000 gallons of slime for the production of Ghostbusters II.5 The formula was developed iteratively by a team at ILM. Dennis Muren and effects art director Harley Jessup created a color animatic on 35mm film while Chuck Gaspar worked separately in New York on color options for Ivan Reitman. Tim Lawrence was assigned to the slime formula for miniature sets. Ralph Miller developed a range of mixtures involving methylcellulose, syrups, oils, and colors. The final formula settled on methocel combined with mica dust, topped with mineral oil. The miniature river set was one foot wide and ten feet long, fed by a holding tank fifteen feet in the air via a team of four portable cement mixers.
For the slime shell surrounding the Manhattan Museum of Art, a full-scale replica of the exterior was built inside a sound stage at Burbank Studios. Chuck Gaspar and crew cut slits in the walls and above the doors, then ran hoses to tanks holding 8,000 gallons of slime, requiring forty people to operate. The hardened shell breakaway used an inner plexiglass plug expanded by an inflated inner tube, which shattered the polymer on cue.
The courtroom slime jar had its bottom cut out and was fed by a plexiglass tube from beneath the table, with an air piston supplying additional slime and an air feed creating the bubbles. Two motors under the table shook the jar; under-table lights added to the tension. A flash was set off for the explosion effect.
For the scene where Egon, Ray, and Winston emerge from the River of Slime outside the museum, the cast was filmed in New York at 2 a.m. in approximately 10-degree weather. The actors were doused with buckets of slime and filmed for hours with no heaters while emerging from a smoke-filled manhole. None of the principal actors complained openly; Ernie Hudson asked Dan Aykroyd and Harold Ramis at one point what they had been thinking when they wrote the scene.
Dana Barrett's bathtub attack was shot on set at Burbank Studios, while the actual slime effect in the tub was filmed at ILM. The tub creature was constructed from dielectric gel (a Dow Corning breast implant material) reinforced with china silk and spandex, operated as a hand puppet by Tom Floutz from under the tub, which was made of white silicone to simulate porcelain and flex on cue.
Development history
The concept of negative emotions manifesting as slime was a late addition to the Ghostbusters II script. Harold Ramis' original idea was that "bad vibes could collect under large population centers and New York was experiencing this kind of seismic level of paranormal activity because the city was about to blow" and that "the people of New York had to be nice to each other because the city could not stand any more bad vibes."6
The August 5, 1988 draft used the term "psychmagnetic" before settling on the final name, explaining it as a new energy composed of P.K.E. antiparticles. In that draft, Egon calculated negative human emotions generate about 65 GeVs per person, and the team considered several songs ("Cumbaya," "All You Need Is Love," "Give Peace a Chance," "It's a Small World") before settling on the Ray Stevens hit "Everything is Beautiful" rather than the Jackie Wilson track used in the final film.
The September 29, 1988 draft had Ray liken the slime to a baby on mother's milk, and an August draft had a character named Lane Walker (a precursor to Dana) electrocute a frog-like slime creature in her bathtub with a dropped hairdryer, a concept the final film replaced with a simpler threat.
In the November and February drafts, only Ray shouts at the slime (Egon does not join in), and Ray and Egon sing "Cumbaya" together rather than relying on a Jackie Wilson recording. The Slime Blower itself was conceived in the February draft: Egon describes it as a "pressure-forced, neutronically metered, fully portable delivery system," and Ray summarizes it as a "slime-blower." Peter sarcastically asks him to keep it under 150 pounds. In early drafts, the baby carriage was not animated by slime contact, but vibrated as if shaken by an unseen hand.
Psychomagnotheric Slime is inseparable from the GBFans.com Slime Blower prop community, since the blower exists to deliver it. Members building Slime Blowers for display and costumes often reference the production formula (methocel and mica dust) as a starting point for creating authentic-looking prop slime for photoshoots and convention appearances.
GBFans.com hosts several sets of community-authored plans for building screen-accurate Slime Blower props, including the Collaborative Slime Blower Plans and Slimer7's Slime Blower Plans.
References
