Even though Doctor Who is primarily a science fiction show about time travel, it used multiple sources of inspiration to create the characters and creatures the Doctor comes in contact with on an almost daily basis. Sometimes, they turn out to be the good guys but more often than not, they face the Doctor and try to hurt him or his companions.
Doctor Who has a rich lore and during its long existence, multiple mythical creatures have appeared on the show. It's easy to forget their appearance thanks to more iconic villains, such as the Daleks or the Master, but that doesn't make these mythology-based creatures any less interesting or scary.
5 The Beast
The Beast is one of the scariest antagonists the Doctor has ever faced in the show. It happened during the second season of the renewed Doctor Who series, more specifically the episodes The Impossible Planet and The Satan Pit. As the second episode's name suggests, the Beast was as close to Satan as they come. Even though it was imprisoned beneath the planet's surface, its sheer size and appearance were still enough to strike terror into the hearts of those who saw it. As a result, the episode wasn't as suitable for the younger audience as other Doctor Who stories.
The episodes revealed that the Beast was millions of years old, having existed even before the Universe itself. The planet turned out to be the perfect prison for the Beast since if the enormous creature ever freed itself, the planet would fall into a black hole. The episodes offered multiple moments of tension and terror, making for a memorable story, and the special effects helped the demonic Beast seem very real.
4 Demons
The Beast might have been the biggest demonic creature that has ever appeared in Doctor Who - but it wasn't the only one. The Third Doctor had faced an alien species from the planet Daemos who looked like demons. The species visited Earth in the past and their appearance made it into the myths. In the story, The Daemons, one of them worked alongside the Master, and it was up to the Doctor and his companion Jo Grant to stop the bad guys.
Interestingly enough, the real villain in the story was the Master, not the demon Azal, making the audience think about the true nature of evil. Another huge demon has also made an appearance in the Doctor Who spin-off series Torchwood and almost managed to kill the immortal Captain Jack Harkness. Fortunately for Jack, he emerged victorious from the showdown.
3 The Minotaur
The Eleventh Doctor has faced many strange creatures, but among the top five would no doubt be the Minotaur imprisoned in the hotel-looking prison. The Doctor encountered the creature in the episode The God Complex. He and his companions as well as other unwilling visitors of the hotel faced their worst fears. The Doctor cracked the puzzle when he realized the Minotaur consumed the people's faith that someone would rescue them from their fears.
Once the Doctor found this out, he came up with a way how to defeat the Minotaur. Even though the Minotaur wasn't on the scene as often as other antagonists, he left a strong impression thanks not only to his appearance but the episode's overall horror atmosphere. It proved yet again that hotels could be scary places, at least in the movies and TV shows. Plus, the audience got the chance to learn what the Doctor and his companions were so afraid of, allowing for a more detailed look into their characters.
2 Vampires
Vampires belong among the most iconic and popular mythical creatures. As such, it makes sense they appeared in the show multiple times. In the storyline, The Chase, the First Doctor, and his companions encounter Count Dracula. Of course, in the typical Doctor Who fashion, nothing is as it originally seems to be, and Dracula turns out to be a robot.
The second time, vampires meet the Fourth Doctor in the story State of Decay. In order to defeat the three vampires who come from species that previously fought the Time Lords, the Doctor first has to defeat their Vampire King, hinting at a clear hierarchy in the vampire society. Of all vampires in the show, these come the closest to the traditional portrayal of vampires. Finally, the Eleventh Doctor faces vampire-like creatures in the episode The Vampires of Venice, but they turn out to be aliens with vampire characteristics, not actual vampires.
1 Werewolves
Where there are vampires, there also have to be werewolves, as horror stories proved multiple times. Doctor Who is no exception to this rule. The most notable example of werewolves is the episode Tooth and Claw in the second season. The Tenth Doctor and Rose fight a werewolf and defeat it but not before it infects Queen Victoria.
The episode combines horror and humor, for example when Rose tries to do her best Scottish accent and fails. It also makes a funny jab at real events and people, since it suggests the werewolf gene continues to survive in the current British royal family!