Casper's Scare School Wiki
Biographical Information

The Underworld



Physical Description




Eye color

Red with yellow irises

Personal Information

Casper (possibly)


Alder and Dash

Kibosh is the tyrannical leader of the Underworld. As a child, Kibosh used to be friendly and had human friends just like Casper, although he eventually was forced to change and become a proper creature.

Kibosh is a prime example of a creature: is fearsome, nasty and disapproves of niceness. Despite his enormous power and scary demeanor, Kibosh isn't out to destroy fleshies and believes in preserving the balance between both worlds.


Kibosh is bulky and green. He has red eyes with yellow irises.


Kibosh has an impatient and demanding personality. He is strict, fearsome and short-tempered and always wants things done his way. Very few people dare to stand up to him and he respects those who do it (like Casper). He is shown to be quite self-centered and loves when people sucks up to him.

Despite his mean demeanor, he is actually amiable and loyal to his people, he cares for (most of) his subjects and has been known to defend them when trouble brews. Kibosh shows no signs of realizing the effect he has on those around him. In his own mind, he is doing what is best for his people, mean and friendly alike.


Kibosh often jeopardizes his relationship with his peers through his fearsome, stern and self-centered personality.


Unnamed human friends

When Kibosh was Casper's age he had two best friends that were humans. It's unknown what happened to them, although it is likely that they grow up and parted ways with him or may have passed away due to humans aging much faster than ghosts.


Kibosh symphatizes with Casper since Kibosh too used to be friendly when he was Casper's age. Kibosh is nicer to Casper than with everyone else and most of the time he doesn't mind when Casper stands up to him since he admires Casper's bravery. However, Kibosh still demands absolute obedience from Casper and that Casper scares people and does his part to preserve The Balance.

It was implied in "What Possessed You?" that Kibosh sometimes spies on Casper to see if he is making any progress on getting rid of his friendliness.



Razznik was Kibosh's servant for two hundred years. Kibosh made him scrub his home's floors, cook his breakfast, floss his ectoplasm, collect sewer worms (Kibosh's favorite dessert) and used him for lightning bolt practise until Razznik decided he had enough and revolted against his master. However, Kibosh doesn't think is his fault that Razznik wanted revenge against him and even believed that he should be thankful for letting him do chores for him. After Razznik was defeated, Kibosh allowed Deedstown's creature catcher to keep Razznik in exchange of the Ghostly Trio.


Alder and Dash

Kibosh is Alder and Dash's boss. Kibosh usually punishes them for not enforcing strict education on Casper. Kibosh once told Casper that the main reason he let Alder and Dash keep their job was for the "entertainment value".

Hedy Hopper

Hedy, like all the Scare School staff, fears Kibosh. In "The Day The Professor Croaked" Kibosh showed that he may have a thing for her as seen when he accidentally kissed her crystal ball.

Casper's gang

Kibosh doesn't seem to have many feelings towards Casper's friends. In "Vote for Casper" he forced Casper to run for Class Representative, not caring that it resulted on Casper having a fight with Mantha and Ra. However, in "Ghost Bust a Move" Kibosh rewarded Casper, Mantha, Ra and Wolfie with a day off school when he though they scarred a gargoyle. In "The Day The Professor Croaked" Kibosh called Mantha and Ra "idiots".

Ghostly Trio

Casper's uncles fear and show respect towards Kibosh, usually complimenting him when they know they are in trouble. Kibosh blames them for not making Casper scare humans.

Graham Bradley

When the creatures were forced to work together with Graham and Jimmy Bradley, Kibosh and Graham were civil to each other for most of the time. ("Power Outage (Part 3 and 4)")


  • Kibosh may not have any friends left as he refers to friendship as "nonsense".
  • Kibosh's favorite dessert are sewer worms. ("Power Outage (Part 3 and 4)")
  • Kibosh appears as an enemy in the videogame "casper scare school: classroom capers".


Major Appearances

Minor Appearances


  • Accidental Hero
  • Casper's New Friend


The image gallery for Kiboah can be found here