1. The Kraken
Tracing its origins back to a giant fish from Norse mythology called the hafgufa, the kraken first entered popular folklore as a titanic octopus or squid spotted by fishermen off the coasts of Norway and Greenland. One 18th century account by Bishop Erik Pontoppidan described it as a squid-like beast so large that when any part of its body stuck out of the water it resembled a floating island. The kraken supposedly used its many tentacles to ensnare ships’ masts and drag them to the icy depths, but it could also create a deadly whirlpool just by submerging itself underwater. Tales of the kraken’s wrath might be embellished, but the creature itself is not entirely fanciful. The legend may have been inspired by sightings of actual giant squid, and some paleontologists have argued that the prehistoric oceans were once home to 100-foot-long cephalopods that fed on whale-sized Ichthyosaurs. - history.com
2. The Griffin
An intimidating blend of two different predators, the griffin was said to possess the body and back legs of a lion as well as the wings, beak and talons of a hawk or eagle. Tales of the flying behemoths most likely originated in the Middle East, but they later became a popular motif in ancient Greek literature. The griffin legend was later picked up in the 14th century in a largely fictional travelogue by Sir John Mandeville, who described the creatures as “more strong than eight lions” and “a hundred eagles.” Griffins were revered for their intelligence and dedication to monogamy—they supposedly mated for life—but they could also be ferocious. The beasts ripped flesh with their razor sharp talons, and they were also known to fly their victims to great heights before dropping them to their deaths. According to researcher Adrienne Mayor, legends of the griffin could be inspired by early encounters with dinosaur fossils. Scythian nomads in central Asia may have stumbled across the bones of the dinosaur protoceratops and mistook them for a bird-like creature, resulting in the myth of a terrifying flying beast. - history.com
3. The Manticore
One of the most forbidding of all mythical creatures, the manticore was a bloodthirsty quadruped that supposedly sported the head of a blue-eyed man, the auburn body of a lion and the stinging tail of a scorpion. The legend of this deadly hybrid first began with Greek authors such as Ctesias, who chronicled it in a book about India. Ctesias and others described the manticore as having three rows of teeth like a shark and a tuneful bellow that sounded like a trumpet. Most terrifying of all, it had an insatiable appetite for human flesh. After using its blistering speed to chase down its prey, the beast was said to slash at them with its claws or sting them with its tail before devouring them bones and all. According to Ctesias, the manticore was even capable of paralyzing or killing its victims from a distance by firing stingers from its tail “as if from a bow.” - history.com
4. The Dragon
A dragon is a large, serpentine, legendary creature that appears in the folklore of many cultures worldwide. Beliefs about dragons vary considerably through regions, but dragons in western cultures since the High Middle Ages have often been depicted as winged, horned, four-legged, and capable of breathing fire."Its back has rows of shields tightly sealed together; each is so close to the next that no air can pass between. They are joined fast to one another; they cling together and cannot be parted. Its snorting throws out flashes of light; its eyes are like the rays of dawn. Flames stream from its mouth; sparks of fire shoot out. Smoke pours from its nostrils as from a boiling pot over burning reeds. Its breath sets coals ablaze, and flames dart from its mouth." - Wikipedia
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