Ray Harryhausen's Creatures Wiki
General information
Type Alien
Status Deceased
Group Reptile
Appearances 20 Million Miles to Earth
Diet Sulfur
Chronological information
First appearance 20 Million Miles to Earth
Last appearance

The Ymir is the main monster antagonist in the 1957 classic, 20 Million Miles to Earth.


After a secret misson to Venus, the solar system's hottest planet, the U.S. Air Force crashed near a small fishing village in Italy. They studied Venusian life-forms called Ymirs, that had a network of spongey membranes inside their bodies to filter out Venus's toxic gas atmosphere of carbon dioxide, sulfuric acid and reptile-like form to allow them to survive in the intense heat with a dwindling water supply. Because of Venus's lack of oxygen and atmospheric pressure they were much smaller on the hostile planet than on Earth. When the astronauts crashed due to a cosmic illness, they brought an Ymir egg sack (which looked like a gooey blob) with them to see if the secret to living on the uninhabitable planet lay within the Ymirs. An opaque case carrying the egg sack was washed up on the village's beach, where a small boy found it and gave it to a scientist. Like a baby bird, the small Ymir hatched from its gooey nest, and grew drastically due to it's body tissue's exposure to terrestrial oxygen. Soon the naturally docile Ymir who had never encountered a human being before would turn violent due to its constant traumatic experiences.


The Ymir was a green colored scaly alien, with a dinosaur-like tail, feet with a humanoid upper torso and arms, along with a sagittal crest on its head. It also had simian-like facial features with large jowls hanging from its cheeks. It constantly increased in size due to tissue build-up as a side effect of inhaling Earth's different atmosphere from its own native world. At the time of it's death, it stood somewhere between 10 to 20 feet tall.


The animal was initially gentle, until it was locked in a cage for a whole day, later to be assaulted by a farmer and his dog, which turned it into a maleviolent and aggressive monster. The once-peaceful beast became hostile with both humans and animals alike after the incident and attacked them without second thought. Then it was chained down by the US airforce upon capture, and shocked with an electirc cage to paralyze it. Upon being donated to the Rome zoo for research, it eventually broke free and was now more agitated than ever. The constantly growing Ymir was on a rampage in Rome, where the creature was finally put out of misery by the military's firearms and vehicles, serving as a reminder of mankind's own cruelty and ignorance.

20 Million Miles to Earth[]

It was discovered on Venus by the crew of the American rocket ship XY-21. An egg-like object, it was collected by the astronauts and placed onboard the ship. On their return ship, something catastrophic happened: it crashed! Plunging into the cold water off the coast of Sicily, the ship and its contents were thought to be lost forever. While Col. Robert Calder survived the ordeal, the alien object washed ashore and was discovered by a young boy.

Hoping it would be worth money, he took it Dr. Leonardo. In the possession of the scientist, the object began to hatch! A tiny, reptilian-like creature emerged from the egg. Leaving the alien reptile in a cage, Dr. Leonardo found the creature had grown tremendously by the time morning came around. Now almost as large as a man, the Ymir escaped its confines and began to hunt for sulfur, its primary food source.

While Col. Calder continued to track the rogue alien, the Ymir moved across the country and continued to grow. It was cornered by a farmer’s dog where it then responded with violence. The commotion gained the attention of the following soldiers whom confronted the beast. After being stabbed with a pitchfork and shot at, the Ymir managed to escape, fleeing toward the sulfur pits of Mount Etna. The creature was then surrounded by the Italian army and trapped within high-voltage, electrical nets. The electrocution sent the alien into unconsciousness where it was then collected and transported to the Rome zoo.

Having grown to an impressive twenty-foot height, the Ymir was continuously studied until a freak accident cut off the flow of electricity. Enraged, the Ymir awoke! It burst from the building and quickly went on a rampage, attacking a nearby elephant. The two animals clashed, but the screaming mammal was no match for the vicious, angry alien. Continuing on with its rampage, the Ymir continued to increase in size and eventually reached the famous Roman Coliseum. Scaling to the highest reaches of the historic landmark, the Ymir was then attacked with heavy fire. It slipped and fell, followed by chunks of rubble. Struggling, the creature was crushed by the falling debris, ending mankind’s first contact with a life from another world .




Ymir Roars


  • Ymir resembles the Thetis Lake Monster.
  • The Ymir's name is borrowed from a primeval godlike being in Norse mythology.
  • Early concept art of the creature depicted it as am enormous satyr-like monster complete with a horned-head, hair covering the body from the waist down and cloven-hoofed feet. These traits were later recycled for Harryhausen's iconic Cyclops in his next film, The Seventh Voyage of Sinbad. Coincidentally, The stop-motion Ymir model was cannibalized to create the said Cyclops.
  • Ymir was unofficially "remade" by creature sculptor Tony Mcvey for his "menagerie"
  • The Ymir was used as an inspiration for the character “Lizzy” in the Arcade game “Rampage”.
  • collection of figure kits, which also included the monster Rhedosaurus from Beast From The 20'000 Fathoms and Gillman from Creature From The Black Lagoon.
  • Ymir's roar is a modified elephant trumpet, like the Ultraman Daikaiju Gatanozoa and the Rebirth of Mothra Daikaiju Desghidorah