The Real Ghostbustershad some of the coolest ghost designs out of any piece ofGhostbustersmedia, from familiar faces to recurring bad guys from the movies. As great astheGhostbustersmoviesare, the animated seriesThe Real Ghostbustersis, in all honesty, probably the second-best thing to come out of the franchise outside of the first film. Part of what madeThe Real Ghostbustersso special was its terrifying cast of spectral ghouls and ghosts that served as the monsters-of-the-week.
Compared to thevillains of theGhostbustersmovies,The Real Ghostbusters' rogues' galleries had a lot more creative freedom thanks to the series' animation. The scares had to be kept somewhat tame due to the family-friendly nature of the show, but the 80s cartoon managed to get away with some surprisingly intense imagery for a Saturday morning kids' series. As a result,The Real Ghostbustersis littered with exciting ghosts and other paranormal entities that gave the wraith-hunting quartet no end of trouble.

10Slimer
The Real Ghostbusters' enduring mascot
Easily the single most iconic ghost inGhostbustershistory, Slimer is an enduring staple ofThe Real Ghostbusters,being the only phantom to return episode after episode as the show’s mascot. The gluttonous green ghost was so integral to the series thatThe Real Ghostbustersgave Slimer his namein the first place, simply known as the Sedgewick Hotel Ghost in the original film. Slimer even goes on to get title billing as the series was re-titledSlimer! and the Real Ghostbustersin the fourth season, reserving a small portion of every episode for his own misadventures.
Slimer is pretty harmless as far as ghosts go, mostly serving as an annoyance to his rival, Peter Venkman, who often calls him “Spud” in the series. Even if he isn’t the most threatening spirit, Slimer’s lovable antics and hilariously gross proclivities for food and ectoplasm are a cornerstone ofThe Real Ghostbusters.He deserves credit for being the only ghost to actually earn a spot on the Ghostbusters team.

9The Grundel
For the most part,The Real Ghostbusterswas a bottle series with a new ghoulish threat on the prowl every week, but sinister recurring spirits like The Grundel occasionally reared their ugly heads. Contrary to Slimer, The Grundel is one of the most insidious and disturbing ghosts ever to feature in the series, often being recalled as a source of trauma for those who grew up watching the show. Clad in a black cloak and hat, The Grundel has a monstrous, elongated face and a raspy voice to suit his spine-chilling personality.
One of the most manipulative and insidious ghosts in the series, The Grundel’s MO is to target innocent children, whispering in their ear and pretending to be their friend only to push them to worse and worse behavior. Eventually, The Grundel’s victims are literally morphed into monsters, forced to grow up unnaturally quickly thanks to his foul influence. Considering what The Grundel represents in a more artistic sense, he’s easily among the most evil spirits the Ghostbusters have ever encountered.

8Samhain
It’s no wonder that a show focused entirely on ghosts and the afterlife would have such a heavy Halloween presence, featuring an explicitly Halloween-themed ghost. Not only that, but the pumpkin-headed spirit Samhain is another one of the closest thingsThe Real Ghostbustershad to a major overarching antagonist, appearing in more episodes than most non-Slimer ghosts and always presenting an alarming threat. Not to be confused with the pint-sized slasherSam from Michael Dougherty’sTrick ‘R’ Treat,Samhain is an ancient spirit revered as a god by other ghosts.
Explained as the progenitor of the original Celtic holiday of the same name that Halloween was based off of (and with an Irish accent to match), Samhain plots with his army of ghouls to take over the world of the living, plunging it into an eternal Halloween night. With a fearsome command of ghastly minions and even time itself, the pumpkin-headed spirit is easily one of the most serious threats the Ghostbusters have ever faced. It’s too bad the live-action films never found the opportunity to revisit Samhain.

7Ghash
A cannibalistic ghost with a memorable presence
Ghash is one of those delightfully twisted and creative ghosts that could’ve only ever been formed as a result ofThe Real Ghostbusters.Appearing early on in the fourth-ever episode of the series, Ghash serves as a memorable monster-of-the-week, apparating as a goblin-like being with a floppy tongue, pointed teeth, top hat, and a massive body shrouded in a black cape. Though he may seem a tad generic-looking and goofy at first, Ghash’s classic camp soon gave way to a more despicable form of horror - Spectral cannibalism.
First appearing as the ragamuffin leader of a ghostly gang that harasses the Ghostbusters on Winsotn’s birthday, Ghash soon unveils his true method of gathering power, the ability to eat other ghosts and absorb their P.K.E. Though he shows off a massive second mouth on his chest hidden by his cape, he actually does so by simply absorbing other spirits into his skin, greedily gulping down other specters to absorb their undead power. A ghost that serves as just as big a threat to other ghosts as the Ghostbusters themselves is a menacing foe indeed.

6The Vathek
Pushed the limits of what could be shown on a children’s cartoon
The idea of theCenobites from Clive Barker’sHellraiserseriesbeing adapted into a children’s cartoon seems quite outlandish on paper, yet this is exactly what the follow-up 90s showExtreme Ghostbustersgot away with thanks to the Vathek. Pushing the limits ofExtreme Ghostbusters' TV-Y7 rating, the Vathek are disturbingly similar to the Cenobites - Extradimensional beings who view torture and surgery as art forms, mutilating themselves and their victims into ghastly new forms. Shockingly, the Vathek were even successful in their pursuits on the show.
It’s hard to believe thatThe Real Ghostbustersgot away with some quite grisly forms of torture and body modification with the Vathek, whose victims were turned into mindless puppets of their own design. From the sawblade-headed Craniac to the headless Corpuscle to the stitch-faced Gristle, the painful-looking forms of the Vathek are endlessly creepy. Nevermind the fact that they managed to turn innocent people into horrific “works of art” like themselves.

5Wat
A shrewd demon with a clever disguise
As great as insidious threats like The Vathek and The Grundel are, sometimes a giant rampaging spectral monster is all that’s needed to make an effective villain. However, the demon Wat is able to lure the Ghostbusters into a trap before unveiling its true colossal body. At first, Wat appears as Mrs. Rogers, a kindly old lady who implores the Ghostbusters to investigate her haunted house. When the investigation turns out to be a trap, Wat reveals its true form, a gargantuan, towering dinosaur-like creature with the peeled-back maw of a naked mole rat.
Wat is the first true demon encountered by the Ghostbusters in the series, making a memorable first impression for the new enemy type. The fact that its name is pronounced “what” also allows for some hilariousWho’s on First?-style antics for the Ghostbusters to contend with, and the demon’s pet infernal bird, an annoying, fire-breathing kookaburra called “Precious” is an added bonus. But the absolute best thing about Wat is the fact that, even in its true monstrous form, the demon speaks in the voice of sweet old Mrs. Rogers.

4The Sandman
Almost put the Ghostbusters to sleep permanently
Another strong ghost appearing early on in the series, The Sandman is a memorable villain who almost succeeds in his plans for world peace. As far asThe Real Ghostbustersbad guys went, The Sandman is almost sympathetic, being an outcast among other ghosts who simply desires to end the war and suffering prevalent in human society. To do so, he begins concocting a plan to utilize his powers to put the entire world to sleep for 500 years, allowing their physically-manifested dreams to walk the Earth instead.
With his gasping voice and eerie proportions, The Sandman is a memorable character with an interesting backstory. His powers to make people fall asleep with magical dust and make their dreams and nightmares come true, includingRay’s beloved Stay Puft Marshmallow Man, also make him a powerful opponent. It’s hard to fault The Sandman for simply wanting all of humanity to sleep off our problems.

3The Peoplebusters
A fascinating twist on the Ghostbusters themselves
Of all the villains to be featured inThe Real Ghostbusters,the Peoplebusters are perhaps the single most creative. Rather than being a team of humans who hunt pesky and dangerous ghosts for the people of New York City, the Peoplebusters are a team of paranormal entities who capture lousy humans who may happen to find themselves in the flipside realm of Boo York City. Taking full advantage of the animated medium, the Peoplebusters have delightfully cartoonish designs that set them apart from other ghouls in the series.
The Peoplebusters' Egon is the most bizarre example, being a skinny, gaunt skeleton with an inexplicable tentacle hanging from his face like an overgrown zit. Meanwhile, Ray is re-imagined as a slapdash Frankenstien’s monster with a hand for a foot, and Peter becomes a jaundiced, withered corpse who can barely hold himself together. As imaginative as these designs are, it’s a shame Winston arbitrarily doesn’t get a Peoplebusters equivalent, missing a huge opportunity for the episode in which they appear.

2Cathulhu
The dreaming Lovecraftian god himself
Far be it for most people to think ofGhostbustersas acosmic horror movie, but the team actually do tackle their fair share of incomprehensible entities from beyond the realm of human understanding. InThe Real Ghostbusters, the team actually tackles the most fearsome and well-known Lovecraftian being of all, the dreaming dread god Cthulu, or at least a version of him, called “Cathulhu”. Despite being off by an extra letter, Cathulu very much resembles the traditional depiction of the H.P. Lovecraft’s most famous monster, described by Venkman as “Godzilla wearing an octopus hat”.
Cathulhu is by far one of the most powerful opponents the Ghostbusters have ever gone up against, coming with his own cult of worshipers and being completely immune to conventional proton streams. It was only through ionizing a roller coaster at Coney Island that the Ghostbusters were able to deliver a charge of electricity powerful enough to jolt Cathulhu back into a dormant state at the bottom of the ocean, only really delaying the inevitable. It’s impressive just how wellThe Real Ghostbustersmanaged to capture the mind-bending horror of Cthulhu.

1The Boogieman
Egon’s childhood nemesis
While the Boogieman may be a fairly generic cultural phenomenon as a term for a vague supernatural entity that preys on children in real life,The Real Ghostbustershas quite a definitive take on the classic monster. Another one of the rare non-ghost entities the Ghostbusters go up against, the Boogieman as he exists inThe Real Ghostbustersis a monstrous being that takes delight in scaring young children witless, with the ability to travel through closets like inMonsters, Inc.Notably, Egon himself was once one of the Boogieman’s victims, making his capture quite a personal matter.
With his massive head, raspy voice, huge ears, ungulate hooves, and 80s mullet, the Boogieman is quite the colorful character for the Ghostbusters to track down. He’s another one of the rare antagonists to get more than one episode to shine, and he certainly makes a big impression with every appearance. The Boogieman’s personal connection to Egon, being the whole reason he started researching the paranormal, makes him one of the more interesting villains in the lineup ofThe Real Ghostbusters.