Scooby-Doo is a classic nostalgic TV series created in the early 1970s. A group of teenagers, Fred (Frank Welker), Daphne (Heather North), Velma (Nicole Jaffe), Shaggy (Casey Kasem), the Great Dane, Scooby-Doo (Don Messick) or the gang, ride in the Mystery Machine to unlock and discover new mysteries.
While some of the monsters are not spooky, there a several spooky, bone-chilling monsters they encounter. The monsters have their own characteristics which make them the scariest of them all. One monster tops them all making this monster the scariest monster they encounter by unmasking the villains.
10 Original Phantom
Season 1, Episode 3 “Hassle in the Castle”
“Hassle in the Castle” has no suspects, adding to the spooky factor. The gang must uncover the mystery behind the phantom lurking on the haunted island. As Daphne falls through a trapped door, the ghost makes its first appearance with evil laughter in the distance.
The ghost shows himself for the first time, and the gang realizes Haunted Isle is haunted. In this episode, there are no suspects which adds to the spooky factor. This phantom lingers in the distance, and the evil laughter is creepy, yet the phantom is not the scariest monster of Scooby-Doo.
Season 1, Episode 13 “Which Witch is Which”
The gang is in their iconic Mystery Machine driving through an eerie swamp as they are approached by a zombie on the side of the road while they are lost. This zombie was summoned by a witch, and the town becomes deserted due to the stories. The gang visits the swamp in search of clues. The witch vanishes Daphne through yet another trapped door. The gang split up to search for Daphne as the zombie and the witch scare them off the abandoned boat.
Unlike “Hassle in the Castle”, “Which Witch is Which” contains suspenseful suspects. The gang must unmask the witch and the zombie who are involved in finding buried treasure. Daphne is found which leads them to more clues to unmask the witch and the zombie. These monsters may not be the scariest monsters of Scooby-Doo, but these monsters are filled with suspense and ghoulish features.
Season 1, Episode 10 “Bedlam in the Bigtop”
“Bedlam in the Bigtop” features a mysterious clown. Shaggy and Scooby become bait to capture the ghost clown, with a suspenseful reveal of the true culprit. The gang encounters two people, who were part of the circus, on the side of the road, and they warn them to get out of this neck of the woods. The circus is haunted by a ghost clown.
The ghost clown begins to hypnotize the gang to be a part of his shenanigans. They believe they have captured the ghost clown, but it was a decoy. Shaggy outsmarts him by hypnotizing him and saving the circus. The identity of the clown is revealed to be unknown due to the fact he was not mentioned before, so this gives a suspenseful nature to this monster creating more of a mysterious reveal.
7 Mr. Hyde
Season 2, Episode 1 “Nowhere to Hyde”
As they drive in the Mystery Machine back home, the ghost of Mr. Hyde is discovered in the back of the van under a blanket. As the gang follows Mr. Hyde into the creepy shack, they fall through a trap door. They fall into a science lab and discover Dr. Jekyll. Dr. Jekyll believes he is the ghost of Mr. Hyde due to his family history.
They believe Dr. Jekyll is not the culprit due to the clues. The comedic relief is the music in which Shaggy and Scooby attempt to escape from Mr. Hyde. They believed it was Helga, the housemaid, and it turned out that Dr. Jekyll was the true culprit under the mask. This monster is based on The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson.
6 Headless Specter
Season 2, Episode 5 “Haunted House Hang-up”
The gang is lost yet again and is encountered by a man with a lantern on a back road. The man gives them directions to the rock n’ roll music festival, and they take the shortest route which is toward the haunted mansion and the home of the Headless Specter. The gang enters the haunted mansion and finds clues to the haunting of the Headless Specter.
The identity of the Headless Specter is revealed, and he invented the Headless Specter to protect his fortune. The gang and the Headless Specter hear the chopping of wood upon further discovery and find a man in a ghost costume which is revealed to be the man with the lantern.
5 Puppet Master
Season 1, Episode 9 “The Backstage Rage”
Shaggy and Scooby find a violin case filled with money. A shadow figure, who dropped the violin case lingers in the distance. Scooby discovers a poodle who seems to be injured, but the poodle was a decoy and the case is stolen by the shadowy figure. Daphne finds a puppet control, and they investigate Pietro’s Puppets to find more clues. They are greeted by an old doorman.
While the puppets come to life, the gang becomes scared. They learn from their search, the Puppet Master is running a counterfeit operation. The puppet master is revealed as the doorman. This episode is filled with puppets; the gang does not know what is real or fake; therefore, the Puppet Master is one of the scariest monsters.
4 Spooky Space Kook
Season 1, Episode 15 “Spooky Space Kook”
The Mystery Machine ran out of gas on a creepy road, and they saw a shack in the distance. They are confronted by a creepy farmer with a gun. Glowing tracks appear on the land and then these tracks disappear. They find themselves a mystery, and they begin to discover the peculiar encounters of the Spooky Space Kook. The gang is in search of clues about where the glowing tracks are coming from.
The gang collaborates on the clues they have found, and they come in contact with the Spooky Space Kook. The gang is stumped as the clues are getting clouded. The gang reveals the Spooky Space Kook as the farmer’s neighbor, which is not revealed to be suspect at the beginning of the episode, which makes this monster spooky.
Season 3, Episode 8 “Jeepers it’s the Jaguaro”
The Jaguaro is a mutant made up of a half saber-tooth tiger and half-ape. The gang must make an emergency landing, and they land in a frightening jungle. Scooby runs into the Jaguaro, and Shaggy and Scooby are petrified by the sight of the monster. There are several suspects within the jungle that could perhaps be under the mask including but not limited to the pilots, and the Australian.
The natives capture Shaggy and Scooby, and the rest of the gang decides to stay in the jungle to save them. Shaggy and Scooby manage to escape as the natives begin to chase them the Jaguaro appears. The Jaguaro is revealed to be the Australian with the help of one of the pilots. The Jaguaro is one of the creepiest monsters because of its uneasy mutant-like facial features.
2 Green Phantoms
Season 1, Episode 16 “A Night is No Delight”
The gang is summoned to a haunted house to read the will of Mr. Sanders as Scooby-Doo saved his life. The two lawyers assigned to the case are Creeps and Crawls. Scooby falls through a trap door tub, and he sees a shadowy figure in the basement.
The gang did not believe him until they heard a noise themselves. They uncover a clue and attempt to draw the shadow in for a trap, but they are unsuccessful. Eventually, they set up a semi-successful trap, and they discover the Green Phantoms are in fact the lawyers. The Green Phantoms due to their bone-chilling, terrifying stature and their wicked laughs make them the second-scariest monster in Scooby-Doo.
Season 3, Episode 1 “Watch Out! The Williwaw”
The gang is visiting Velma’s, Uncle Dave, and they spot a glowing monster in the sky. The lodge is deserted. The Willawaw is a menace to the lodge; Uncle Dave was chosen to be a sacrifice. The natives describe the Willwaw as a “fiery flying monster with a face like an owl.” Scooby and Shaggy discover clues to determine the true identity of the Willawaw.
There are no suspects other than the natives which creates more of a spine-chilling effect to the mystery. The gang has difficulties capturing the Willawaw, but they eventually capture it and discover it is in fact a trio of the natives. The Willawaw is the scariest monster throughout Scooby-Doo due to its nightmarish features. They are eldritch creatures, and it is the most terrifying and unpleasant monster.
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