While Doctor Who is a classic adventure series, more often than not, it leans towards the horror genre. It includes classic horror story tropes and horrific monsters to go with it, haunting viewers' nightmares. The classic series presented positively scary narratives, and the antagonists of those stories were all sorts of horrific creatures. Some were visually scarring, while others attacked the psyche.

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The great thing about Doctor Who is, that people with a weak stomach can enjoy it (avoiding some of the more scarring episodes), while horror fans can find some excellent episodes true to the classic genre as well. Fans have been pondering about which monster would be the one to take the cake regarding scares, and surprisingly, most people could agree on the top three scariest monsters ever to be featured in the classic series of Doctor Who.

9 Robots (The Robots Of Death - 1977)

Doctor Who - The Robots of Death

"The door is not a barrier" according to the homicidal robots featured in the 1977 episode The Robots of Death. While Doctor Who is rarely classified as horror, this episode doesn't shy away from traditional horrific scares. In this case, the build-up to inevitable and brutal death is the main scare factor. Some scenes are especially hard to watch, where the episode shows as these robots strangle the life out of people with an unsettling calmness.

The repeated image of these red-eyed lifeless robots coming towards the screen with outstretched arms is one that many will remember for years to come. Those who grew up watching the classics of Doctor Who will remember these scenes like it was aired yesterday.

8 The Osirans (Pyramids Of Mars - 1975)

Doctor Who "Pyramids Of Mars"

In Pyramids of Mars, viewers are introduced to Sutekh the Destroyer - the last of the Osirans - who wants to be freed to "bring his gift of death to all who live". His presence and power are very unsettling and overwhelming, as he embodies the destroyer of all living things. There are several scenes in which the true power of Sutekh is demonstrated, making the villain even scarier than before.

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By the third part, viewers know that even Sutekh's henchman is to be feared, so there's no telling what the actual beast is capable of himself. When the Doctor confronts him he's able to casually overpower him showing his dominance. Seeing the protagonist be undermined like this elevated the terror even more as the episode continues. In the classic series, he's one of the most notorious antagonists, and most unsettling monsters, as he's able to stump and overpower the seemingly unbeatable Doctor.

7 Autons (Spearhead From Space - 1970)

Doctor Who "Spearhead From Space"

Doctor Who has some downright brutal scenes to encapsulate and demonstrate the villain's powers. One of the most awful monsters is the Autons, plastic lifeless dummies who brutally shoot down anyone in their way. Only the exterior will bring shivers down the viewer's back, as there's nothing more terrifying than a weird bald plastic thing coming to kill you.

There's one specific scene in Spearhead from Space that makes everyone pause the movie and take a deep breath. When Ransome (an employee at the plastic factory) tries to hide from the creatures in a tent, and an Auton simply slices through the fabric and steps through to get closer to the person. It's horrific, unsettling, and because of the lack of CGI, seems all too real.

6 Yeti (The Abominable Snowmen - 1967)

Doctor Who "The Abominable Snowmen"

The Yeti monster first appears in the series in The Abominable Snowmen episode, but an even more notorious episode featuring them is The Web of Fear released in 1968. The episode is extremely well-made and demonstrates ghastly realism to the point where people wonder if it was shot on location. It takes place in the London Underground, and the episode perfectly combines the real with the fantastic elements.

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Through this episode, viewers see and experience the horror that is paranoia due to the dark enclosed (an all too familiar) environment that is the underground tunnel, spiced with the horror of seeing characters being killed off. The pièce de résistance is the attack of the Yeti which makes the scene incredibly scary.

5 Malus (The Awakening - 1984)

Doctor Who "The Awakening"

The power of Malus is not even as scary as the image people associate the name with. This creature has the ability to feed off of fear, hatred, and overall negative energy, ultimately using it to his advantage. But once viewers get a glimpse of this horrifying creature, they don't even care what its powers are.

An awful, giant face leering through church walls is enough for people to go "NOPE" and just look the other way. In a later scene, it appears inside the TARDIS which just feels wrong, not to mention its repulsive exterior. Even during death, it starts spewing a disgusting green slime, meaning that in any state, this creature is horrible and just needs to go away.

4 Kandyman (The Happiness Patrol - 1988)

Doctor Who "The Happiness Patrol"

People who grew up watching the classics of the '80s will remember the eerie face of the Kandyman, the awful antagonist of The Happiness Patrol. For some fans, the monster is simply hilarious and too silly to take seriously, while for others it's the source of nightmares.

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The Kandyman looks ordinary enough - like the mascot of a candy store -, with one very important difference: he enjoys torturing people. The practice of turning kid-loving characters into the center of a horror flick is not news. It happens to clowns, dolls, toys, and yes, mascots each day, and never seizes to unsettle viewers. The sight and sound of a seemingly sweet character running aimlessly and screaming will always be scary.

3 Mara (Kinda - 1982)

Doctor Who "Kinda"

Abstract visions, unanswered questions, and slow descent into madness are key factors of this episode. While Mara might not be the most terrifying creature visually, the added terror of the episode's story will make the presence of the monster overwhelming for viewers to handle.

It exists by taking over and haunting its host's dreams, resulting in the weird and disturbing mania present in the episode. When the episode first aired, fans didn't like Kinda, supposedly because of its weird style. Over time people began appreciating the story, and critics applauded its contemporary storytelling. Today, it's known as one of the most fascinating episodes of the series for many reasons, one of them being the unusual and frightening creature, Mara.

2 Cybermen (The Tomb Of The Cybermen - 1967)

Doctor Who "The Tomb Of The Cybermen"

The Tomb on the Cybermen puts a Doctor Who-twist on a well-known monster story. Its structure is one that can be used as a template for all mummy stories, and still, Doctor Who does it impeccably well, resulting in a surprisingly fresh take on the classic story.

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The build-up to the monsters, the tension of the battle, and the conclusion are all very satisfying, and on the surface, the episode seems and feels like an everyday Doctor Who episode. The Cybermen have since become a staple of the franchise, and fans of all ages know - and fear - the villains all too well. One of the most famous episodes of the franchise, The Tenth Planet featured the monsters as well.

1 The Daleks (The Daleks - 1963)

Doctor Who "The Daleks"

'80s horror is known to be extremely violent, yet never too gory or over-the-top. While the infamous monsters called the Daleks were first seen in the 1963 TV story The Daleks, Resurrection of the Daleks (1984) is a better example of this. It has one of the biggest body counts in the history of Doctor Who, and still, it remained less gory, and instead more shocking or unnerving.

The Daleks aren't visually terrifying but are built to kill. They were an alien warrior race surrounded by massive armors. They're one of the most memorable villains of the show, and most people rank it number one when asked who is the scariest monster in the franchise. After all, several Doctor Who episodes revolve around psychological terror instead of gore and scare.

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