Ghostbusters Wiki
Ghostbusters Wiki

A Class 5 Entity (that is part of the Classification System) is a mid-level specter that takes on a non-humanoid form. The most well-known of which is Slimer, the Full Roaming Vapor who haunted the 12th floor of the Sedgewick Hotel in New York, New York.


Primary Canon


List of Entities

Ghostbusters: Afterlife

List of Entities

Secondary Canon

Ghostbusters Role-Playing Game

Class V: These are ectoplasmic manifestations of definite but non-human form. Speculation includes the theory that Class V's are formed from emotionally-charged events or as side effects from ritual summonings. (The spud Peter Venkman talks about so much was a by-product of the rituals that a cult held in the Sedgewick basement.) These typically require extensive Proton Pack implementation to eradicate.

Class 5 Entities are ectoplasmic manifestations of definable but non-human looking creatures with some form of intelligence. Speculation includes theories that Class 5's are:

  • Former human remnant ghosts which have 'devolved' or 'mutated' into other forms as they slowly lost their memories of their former selves
  • Ghostly entities from another dimension that entered our world through interdimensional portals
  • Simply born out of ecto-energy into whatever form they wear now
  • A side effect from ritual summoning
  • Byproducts formed from emotionally-charged events such as murder and suicide

List of Ghosts based on The RPG Guidelines

  • Slimer

Ghostbusters: The Video Game (Realistic Versions)

List of Entities

Ghostbusters: The Video Game (Stylized Versions)

Via Tobin's Spirit Guide: Slimer

I have seen vaporous manifestations with vaguely humanoid faces, but grotesquely distorted bodies and spindly, nigh-useless appendages. I believe these malformed entities are manifestations of raw psychic energy, and could represent some of the primal vices like gluttony or rage. They don't seem to be bound to any physical restrictions and since they have no specific tie to a human spirit it eludes me as to how one would deal with such a manifestation.

List of Entities

IDW Comics


Class 5 entities are fully formed manifestations most often the by-product of highly charged emotions and ambient psychokinetic energy. They can have human characteristics like limbs and a discernible face but otherwise has a non-human form and lacks personality and/or intelligence. [1]

List of Entities

Animated Series Class 5

The animated series doesn't follow the same rules as RPG and can go higher. To read more about it go to Animated Classifications.


  1. Ghostbusters 101 Class Notes (2017). IDW Comics- "Ghostbusters 101 #1" (2017) (Comic p.23). Class Notes reads: "Class 5s are fully formed manifestations (as opposed to a floating pair of eyes, for example) that may have human characteristics, but a decidedly non-human form overall. A prime example of this is the green ghost in the lab's observation tank. It has limbs and a discernible face, but otherwise shares little in common with a humanoid. They can exist without personality and discernible intelligence, and are are most often the by-product of highly charged emotions and ambient psychokinetic energy. (In theory, studies are ongoing.)"